Thanks Kross! That's really my objective, build something decent, not anything fancy or top of the line, but something that really gives me good SQ without issues. I got tired of my old crappy setup which everybody told me it was ok (just co-workers who don't really know much about car audio) but I've listened some systems that sound amazing and when I listen mine there was a HUGE difference. So, with all your help of everybody here and a little research I guess it wasn't necessary to spend a small fortune to get a decent setup:
Hifonics bxi606 $175 shipped
Kicker zx650.4 $186 shipped
PG RSD 6.5 $95 shipped
I just need to buy the cables now and distro block, oh and the L shape RCA's.
I'm gonna keep my 10" CVR's which I'm gonna give them 300w @1 ohm each side.
About the HU I think I'll keep it. I hope the whining noise is not a damaged HU, I'm gonna ground the RCA on the back of the unit to see if that fix the problem, but I was worried about the comment everybody says an internal fuse might blow when you do that.
I don't really want to upgrade HU now because I would really like to get a Pionner NAV system in the future, but I don't know.
BTW I'll check the prices on 1/0 gauge and see if I can afford it, after buying those 3 things I'm pretty much broke right now