I've been ripping my CD's to MP3 using LAME, with -preset fast standar (or -V 2), since audio listening tests find that LAME with these settings is transparent and as good as top quality Ogg Vorbis or AAC, and MP3 is still a bit more supported than AAC.
Lately, I've been running out of space on my iPhone and I'm considering to start using AAC to compress my music, but there is no point using iTunes+ (AAC at 256 kbps) or AAC at 192 kbps since that would still occupy the same space. It should be AAC at 160 kbps or 128 kbps, I guess.
iTunes has an option to convert all my music to AAC 128 kbps when synchronizing the iPhone. Is 128 kbps AAC equivalent to the LAME encoding I've been using? If so, I could use that option, while I re-rip my collection to AAC 128 kbps.
What else would you recommend?