This question is probably posted a lot so feel free to reply with a link to a guide or something I can read myself.
My old Iaudio G3 died. I want to replace it with something that either natively supports ogg vorbis (FLAC is a plus, but not really necessary) or will take RockBox. I've heard that the lithium-ion batteries that are in almost all new players will die after a year or 2, and a few rechargeable AA or AAA batteries cost significantly less tan a new player. So I'd like to get one that uses replaceable batteries (or some assurance that a player not using them will still last a while). Don't care if it: plays video or not; does AM/FM or not. Voice recording is nice but not essential. Prefer flash-based, 2 to 4 GB (and/or SD), under $150.

This page is probably a good starting place, as it includes info about how well rockbox runs on the various units:
http://www.rockbox.org/twiki/bin/view/Main/BuyersGuide

I read their page listing the current ports. I found I needed more to go on since it only runs on a few lines of DAPs.

I have a Meizu Miniplayer M6, bought from a legitimate trusted seller of the units on ebay for £100 in January.

4GB flash (I think there's 8GB available now).
USB removable drive so no proprietory software needed.
MP3, FLAC, OGG Vorbis
Photos
Xvid and Divx video
Amazing battery life (I get about 24 hrs with the latest firmware)
Voice recorder
FM radio
Custom skins/wallpapers

Meizu's a chinese brand and their website's a bit slow loading in my experience, so do a search for some reviews on the Meizu miniplayer and you'll be impressed by the write ups.
Or take a look at www.meizume.com

HTH

All Rockbox targets that can play Vorbis use LiPoly batteries. However, your intuition here is misguided. Lipoly batteries are extremely cheap, so there is no real cost savings verses NiCd or NiMH batteries.

If you want flash, you're going to be looking at an Ipod Nano 1G (1-4GB) or Sandisk Sansa (2-8GB expandable via MicroSD). I'd recommend the Sansa in this case, though its still a little rough around the edges at this stage of the port, and battery llife is still mediocre (~12 hrs).

You heard wrong about li-ion batteries. Well, it depends on how they are used. Most li-ion batteries will last for 500 complete charge cycles. This means that you can completely drain and charge the battery up to 500 times. After the 500 charge cycle, the battery will begin to lose its ability to hold a charge. I have a 3G iPod that still holds its 8 hour charge and it is about 4 years old, same with my 4G iPod and it is about 3 years old now. It all depends on how you use your unit. If you keep its battery fairly full the majority of the time, then you can easily get 3-4 years out of the battery before it begins to lose its ability to hold charges. I wouldn't worry about the battery in these new units. Besides, you can pick up replacement batteries for popular players and install them yourself. I think a replacement battery for a 3G iPod costs $35 which isn't a whole lot at all.

Look at the features of the player, don't focus on the battery type. Otherwise, you will probably be stuck getting a not so good unit just because it uses AA or AAA batteries.

Interesting point. One of the reasons I've kept my particular mp3 player for so long (Archos Recorder 60gb) is because I can go to Best Buy and walk out with new batteries for about $12 right away. I really like that convenience.

Yeah, that is why I hesitated purchasing my 3G iPod. Actually, I purchased a 20GB Rio Karma but it had a faulty hard drive. I then exchanged it for another Rio Karma and it too had a faulty hard drive. I then exchanged that for a 40GB 3G iPod. I was hesitant in purchasing my Rio Karma/3G iPod because I had a Rio 600 (with an amazing 96MB of total space!) that used a Ni-MH rechargeable AA battery that I could easily replace for $2. However, these newer li-ion batteries are pretty spot on and the market has shifted towards them. I was looking at Best Buy the other day and all the DAPs they had on display used li-ion rechargeable batteries. I went to Wal-Mart and they had a couple that used one AAA battery but it was extremely limited in terms of features and build quality.

I wouldn't worry about the battery as long as it is a li-ion battery, you should be fine and the device should last you at least 3 years (as long as you follow the charging steps in its manual).

Thanks for all of the replies. I'm still somewhat partial to Cowon, but I'll check out the Sansa and some of the others I've seen.
What are most 'audiophiles' going for right now, when it comes to flash based players? And where?

If you can hold off until August, Meizu plans to release an Meizu 6SE, which is slimmer than 6 and comes with 8gb Flash for $130.

http://www.anythingbutipod.com/

Site I use quite often to see what is out there because it has all DAPs under the sun...except for iPod of course but the info on iPod is plentiful as it is.

FYI, for those who didn't know of course, Apple's iPod is a Chinese DAP too. Considering it is made there and the only thing American is the design.

After looking at some M6 players, I have to say the price per GB is really good So are the features. I think I'm getting a Meizu.

Maybe check out the Cowon D2?

Specs:
* Audio Playback formats: MP3, WMA, OGG Vorbis (up to Q10), FLAC, WAV, APE
* Video playback format: predefined format (up to QVGA @ 30fps) through conversion software
* Picture/text viewer (JPG, TXT)
* Folder Limit: 500 folders and 5,000 files
* Built-in FM radio + recorder
* Built-in voice/line-in recorder
* Display: 2.5 inch 16 million color(24bit) TFT-LCD Touch Screen
* Resolution: QVGA (320x240)
* Built-in memory: 2GB, 4GB
* External memory (SD, MMC) Card Slot
* PC interface: USB 2.0 High Speed
* Power: Built-in Rechargeable Lithium Polymer Battery
* Playback time:
Music : Max. 52 Hours Continuous Playback
Movie : Max. 10 Hours Continuous Playback
* Charge time: About 3.5 hours by adapter, About 7 hours by USB
* S/N ratio: 95dB (A-Weighted), frequency Range: 20Hz~20KHz
* Max Output: 16 Ohm earphone : 37mW + 37mW
* Size: 78.0 X 55.4 X 16.6 mm (W x H x D)
* Weight: 91g (Include Lithium Polymer battery)

Here is an excellent review of it.

Really? August? Damn. I want one now, but maybe I can wait 3 months.

Does anyone of those do gapless?

Or no one cares?

To me, that is the MAJOR reason to look no further than iPod.

To me, true audiophiles will settle for nothing less than a gapless playback-capable player.

you know that video ipods are gapless, right? and you can use rockbox also.

Except that I don't think Rockbox is gapless on the iPod. It might be but I don't think it is.

All formats that are physically capable of gaplessness have always been gapless on Rockbox except on the old Archos targets.



" look no further than iPod" == "buy an ipod because it supports gaplessness".

If you want Vorbis support, take a look at the Samsung DAPs.

I have a Samsung YP-Z5 1GB, but this model seems to be not sold in US (I'm french).
Features of the YP-Z5 :
- native Vorbis support
- fully gapless for MP3 AND Ogg Vorbis
- support playlists
- display JPEG pictures
- FM tuner
- 9-band customizable equalizer
- 45 hours of autonomy with the new firmware

Unless you have to sacrifice SQ to get gapless. A true audiophile would never do that.

I've still got a working Rio Karma along with a 40GB Zen Xtra. I'm looking for a new dap, nut haven't
found anything I like yet. All the new stuff seems to be flash based or adds video. Hoping for an X5
replacement that has what I want. Sound quality is at the top of the list, I need at least 60GB (or more),
and it has to have user replaceable batteries. I'd like line level out, support for flac, and gapless.

Depends on the gap disturbance. On an Ipod Shuffle it's a noisy gap of 300-500 ms, while on a Cowon D2 it's a a silence of a few milliseconds that don't annoy me at all ( I even splitted some of my "one-cd" mp3 because .cue files are not supported yet ).

Yeah that is a problem. I wish .mp3 and .flac files with the cue sheet were supported on more portable players.

There's a plugin for winamp that treats the .cue file as a sort of playlist which is pretty cool.

Rockbox actually has cue support, but its not too useful since it supports gapless and playlists anyway. Plus CUE has trouble seeking in some formats in VBR files do to historical reasons.

Wow. Thanks for all of the replies, more than I expected. Ended up ordering an M6 due to reviews and the spectacular $/GB. The D2 was actually my first choice, but it was a bit pricey for me.