the 12' are VERY musical, and two will suffice for most low notes, but the 10's youll need 4 of them (and yes four will fit) as will the 2 12's
if you are a heavy bass head, they may not be the best bet
may want to look into the dayton reference 12's HO version supposedly some great sounding woofers, and they are on sale for like 105 each from partsexpress.com
http://www.partsexpress.com/pe/showd...number=295-466
they need power though so keep you eye on that if you already bought the amp
not really mainstream, but the specs, copper weight,and build qaulity are far better than most you can buy in your local CC
good luck