As everyone has already mentioned Gary is incredibly friendly and great to deal with. He answered all of my questions. I put my PA2V2 with my Clip+ (Rockboxed) and Ultrasone Pro 900. It sounds really great and there is a noticeable SQ improvement - especially in the bass. It has a warm presentation which some like and some don't.
What's your source, broski?
Edit: One issue though. The cable that Gary sent me stopped working properly within a few weeks. So I ordered another cable from Headroom (a 4 inch mini to mini right angled on each end). So basically I bought the amp and spent money on the cable too. I don't know if that is a reason not to get the amp though. I mean, it is a great amp and Gary offers it for a killer price.