Thanks for the comments guys. What do you think of these subs?

http://cgi.ebay.com/2-ALPINE-SWRM100...item2a07fa3cd2

Those are what I have in my boat. They sound about as good as free air subs can. I'm putting about 250watts to each one. I've had mine almost 2 years with no issues and no complaints.

Running 6 7" Alpine speakers and a single 10" sub off of a 6-channel JL amp. So far, so good, sounds great!

Focal are VERY GOOD, but I guess just like with an OL you pay for that quality.

For amps stick with class D, they are much more efficient and will drain less battery (doesn't mean it still can't die haha)

My setup is all Memphis, not bad for the cost. The JL amp (slash series) I had I couldn't turn up off the battery because it couldn't get enough current.

put in a new system with JL amps this spring, really like them so far, great sound and suprisingly little power use, can run them hard all day and not drain the batteries

Slash series or digital?

Their new digital line are great, the slash are huge current hogs. All are good amps.

MHD 750/1 and currently a 600/6, waiting on the MHD600/4 on backorder

I've got the exact same setup going in later this week, what are you using for speakers? Any comments, complaints about these amps?

We run JL in the Outerlimits, all speakers and amps, very nice setup. We also have some Focals in the Formula, the sound is unreal but you do pay a premium for it. I wouldn't be afraid of Alpine, always use to run those in the car audio days. Would recommend any of these. Good luck with the system.