Sounds as if you want the 'best' filter out there. The XP3 should be doing you well, but if you want better, I think you are going to have to go after an Eheim.
I have the 2026 and LOVE it. I researched mine before I purchased it and found one that came with all the setup options and media included.
I am currently running: XP2, Eheim 2026, and a magnum 350. The 350 is byfar the worst cannister filter I have owned, though I like it more with any HOB
that I have every had.
The XP is awesome with it's price, but my Eheim can't be beat. Much nicer filter then the XP.