Alliance is good because so much support for everything Touchwiz and all the change options. I like AOSP look as well. I do so much. The think I miss the most is the native quick tiles. The ones in Alliance are just not as functional and easy to use as Eclipse. I'm trying to get it working with MAPPZ Quick Settings with a right hand shade pull down and tiles I want but it is not the same.
Similar performance. The only thing taking me to Alliance is really good voicemail support. I've missed a few calls and that is not acceptable.