I'm using 3.92 ver. I know this is the latest bugfree version.
I'm wrong?

Lame 3.90.2 compiled by Dibrom is recommended here because it has been most extensively tested and tuned by listening tests (and it's fairly fast at encoding). Later versions, by number aren't necessarily better for safe encoding with the alt-presets and may be a little slower, though they are working hard to make improvements. Perhaps a future version will receive extensive testing and become recommended here eventually.

You'll find the information and links on the sticky threads/FAQ, so I won't repeat it here.

3.93.1 is the latest bug free version, but not necessarily the best from a quality point of view as
DickD points out.

I'm using 3.93.1. It has been introduced December 1 2002, four month ago. Havn't read anything about examples, where 3.93.1 fails over 3.90.2, so if you think four month is enough of "real life"-testing...

I would't re-encode anything, regardless if you use 3.90.2, 3.92, or 3.93.1. Only 3.93 sucks.

there shouldn't be any audible differences between 3.90, 3.92 or 3.93.1. just don't use 3.93 (original release) because there's a big bug in it.

some will tell you to use 3.90.2 because it's the most tested version and sound quality MIGHT have decreased later on but nobody was ever able to prove this theory.