I would stay stock if i were you.i got ripped on Ebay, luckily got my money back, sucked it up and drove to a Premier dealer closest one was 90 miles away. Bought it at full retail, and i have pioneers full 2 year warranty. I'm fine with that i have the worst luck in general, I had the only Eclipse 7000 that had lost pre amp output. ahh that was bought authorized as well. . .
They don't sell them anyway. Crutchfield doesn't carry Premier series at all.
I bought at WoofersEtc. Don't know if I'll ever have issues with them honoring warranty, but for time being, they were super fast and easy to deal with. No issues. And they price match other websites.