I tried the FUN, IMO the HDP sounds cleaner, if that makes sense. The separation is noticeably different.
Also the HDP looks a lot nicer.
Then again, I'm using with ATH-M50, HD-25, and HD-600. If you have AKGs, from what I've read you might want to check out the FUN as the bass in the HDP isn't as pronounced, it's more neutral overall.