Its pretty rare to find Solo L7s in anything but DVCs. Yeah, you definitely want to have enough power...when I first started out, I learned the hard way, blew an Orion capable of 700watts max by only pushing it with about 200watts from a bad Sony Xplod amp...of course you want to turn it up more to make the bass louder, this causes clipping (trying to get more power/bass/sound than you have)-which is the single handed worst destroyer of subwoofers in the industry...
you should be able to find one of those Alpine MRV-1507 on ebay for $350 or cheaper...they are beasts. I've dealt with 2 of them (1 was stolen along with my old car, but good enough to go back)
If you do go with 2 Mono amps, that means you also have to have twice the wiring...two power cables (most likely starting with 1 cable going into a split block), two ground cables, a connecting RCA set, splice a second line off the existing remote cable...all this is probably what is suggested in Crutchfield's "Other Items" list...Pushing that much power, you'll want a Farad Cap as well, otherwise you will have some fading headlights and electronics...
5 Speed Manual
Alpine CDA-7895 Head Unit
12" Alpine Type-R, sealed box
Pioneer 400w amp for $20 at a yard sale (to replace my fried MRV-1507)
Infinity Kappa 4" 2-way speakers(rear)
Infinity Kappa 5.25" component speakers(front)
Debaffled airbox, K&N filter
Tracked Mud on carpets
Shampooed and cleaned carpets