This is one of my fave compressors especially for mastering. I have got a few including the amazing API 2500 but this is just sublime. This new version is very good. Also V2 stays behind and you get to choose between V2 and V3 after you install. There is a stack of improvements including the adjustable GUI and all. This can be set for just super transparency and I mean clean and transparent. Which in many high quality mastering situations where you don't really want to change the sound much, is perfect for this role. I use Punch and Smooth a lot but the others are fantastic too.