Yeah, I'd go for the 510, and trade in your subs too.
You'd better trade up because the 510 will smoke those baby JL's.

Seriously, I'm a big fan of bigger subs and more power.
I have 2 CVR 15's with a bridged 5100T on Each for 380 wrms each.

And I want more.

I hear Kenwood decks are good, my future son-in-law has one and loves it.
Personally i like alpine. I had problems with an old pioneer, but that was a long time ago. Eclipse and Blaupunk and clarion have good reputations.

More than make, you should look at what features and functions you need. Don't get caught with a deck without all the outputs you need.

Set a bottom line. If you decide you want front rear sub RCA outputs and you need built in time alignmet, mp3, ipod, etc., then look only at those that have what you want.
A lot of people get stupid low prices, then wonder why it doesn't have all the stuff they need. Then they want adaptors and add ons to make it do everything they should have had in the first place.

__________________
Alpine CDA-9887, TUA-T500HD, CHA-S634, CHA-1204 & KCA-410C
Pioneer TS-A6981, 6 x GM-5100T
Kicker 2 x CVR15,
MBQ RCE-216
PG MX2
Soundgate LanStar1
PAC SWI-ALP