I can not  speak to the Aaen's performance as I have never run one. But I have owned and run Stock, Bills, PT, and CT.

The bills was like everyone says torquey and flat but better than stock.  The PT was better than the bills.  The CT was MUCH better yet with More power than all the others I have tested with more power everywhere but not a real high rev pipe.  Great all around snappy mx power but not a real high rpm screamer.  Still  hands down better than the others I have run.

I can not compare it to the Aaen or the newer bread of pipes.  From what I have read from many others I would say the aaen would be far  far far better to the PT.