After trying out AudioCodex, I prefer the "lean" approach of Vox - even though it has EQ, compressor, ... settings - including a less than useful phaser/phaser (unless you are a DJ or something).

The more so since it focuses on the essentials; it plays all files formats, it is very stable and the price (free) is sure alright.

If it had the capability to use Audio Units, it would be perfect for me.