Best bitrate for online streaming (aka internet radio). Options

[uart]

I know that for most of us, as storage capacities have increased we've generally become less concerned about being economic with the bit rates of our encoded music formats. One area however where I"m still kinda interested in bit rate economy is when listening to internet streamed music such as "internet radio". The reason is simple, I've only got 10GB/month downloads and I'd prefer to not use more than about 30% of this for online listening, particularly as it's something that I'm often just using as "background" music.

With that said, what bit-rates to others here find suitable for online radio purposes. Personally I seem to find 64 kbps HE-AAC to be roughly equivalent to FM radio, though that's only a subjective judgement. Just wondering if anyone knew of any tests to establish what codec/bitrates are roughly equivalent FM radio for typical music listening purposes?

Thanks.

[uart]

I felt bad about so many subjective opinions in the previous post, so I just made a few blind comparisons. Sorry it's very brief but I only had limited time. I wanted to compare aac(sbr) 64kbps (nero @q-0.25 as that's the only encoder I've got) with various bit rates mp3s, upping the bit rate until my blind "which I prefer" picks became random. In the end though I only tested Lame(3.99r) at V9 (69 kbps) and -V7 (99 kbps) against the aac (sbr at 65 kbps).

With lame -V9 (about 69kbps) it was 100% (essentially no randomness) that I preferred the aac.

With lame -V7 (which was about 100kbps) it became pretty random as to which I chose as "best" each trial. Admittedly it was a very limited test, but it did tend to back up the notion that aac-sbr at 64kbps is roughly similar quality to mp3 at around 100 kbps. At least to my ears.