First off, you said you are running 3 CVR's. What is the coil config for each sub?
When I ran my PDX at 1.4 ohms it would play fine, but if I turned it up too loud or if at a certain volume where it did fine with say a 50 Hz note in a song and it played a 32 Hz note in a song on the same volume, I would have problems with the amp shutting off. I set my gains sort of by ear, but mainly used the volume on the HU as a limit, took some time to figure out what is a reasonable limit I can play my subs at.
The PDX isn't an amp that you would put in a luxury vehicle as you mentioned, but more of an amp that you wouldn't abuse. The RF will take some abuse. It will also stay VERY cool, good choice on an amp.
And to those telling him to go buy off
eBay, sure it's cheaper, but what would he do if something were to happen to the amp or any of his other equipment he purchased from an authorized dealer? Even if he can exchange the amp, he would have to ship the amp at his expense, wait several days, and hope they send him a new one, not a refurbished one. Buying from a dealer, you have the convenience of taking the amp when you want and getting it swapped for a new one.
Sure, you spend more money, and you don't need warranties if you know how to treat your equpiment properly, but if for any reason it was a manufacturer defect or that rare chance of something out of the blue happening, you will be covered. You end up paying more if you buy an amp from
eBay, it gets messed up and then buying another. It all comes down to how much security you want. Personally, I have bought plenty from
eBay but mainly because I was buying quite a bit and if I bought from a dealer, it would have been out my budget. It's a game or risk we all play should we go the
eBay route, but realize its the dealers who help keep the manufacturers alive.