Just went from ICSSGS (onecosmic) 4.2 to this rom:
ICS333 RC1.1 by Team 3xtr3m3
its an ICS 4.0.4 ROM which works brilliantly. I switched from ICSSGS because they are still stuck on ICS 4.0.3 although I must say that one works just fine too!
its an AOSP rom, meaning that its trying to be as close to how google releases ICS themselfs. They made some enhancements, like a brightness slider in the pulldown menu etc, but they really work well and they dont "over do" it with extras.
Together with the newest Semaphore kernel this works like a charm.
Link to the ROM for more info:
Link to Semaphore kernel:
I can really recommend this combination.
Good luck with finding a ROM that works well for you!
Ps. It is kinda hard to define which rom is "best". Different Roms offer different kind of stuff. I like my ROM to be as clean as possible with not to many frills. Other people might want to have buttons for everything
. Its just what you personally prefer. I suggest you read the ROM threads in the android dev section. Most of the time you can get a good glimpse about what a certain ROM offers and how stable or buggy it generally is by the first post and the suggestions / replies that are posted by users.