subsam

hey guys, im setting up a surround system and i need help deciding what i should get. i already have the shelf system, and i have an accomodation with Klipsch. My amp is a 480Watt Yamaha, and i'll use my floorstanding Technics ( 240w Input/120w @ 8ohms ). Anyway, what i really need help with is picking out the other speakers. First the subs. Should I get one KSW-12 or two KSW10s? It'll be in a small/medium sized, rectangle-shaped room. Any help at all would be greatly appreciated. im looking to spend around $600 for a center, the sub(s) and the surrounds. here's the prices i get: sb-1 pair- 100 sb-2 pair- 140 sb-3 pair- 180 sc.5 each- 72 sc-1 each- 112 sc-3 each- 140 ss.5 pair- 120 ss-1 pair- 160 ss-3 pair - 220 KSW-10 - 160 KSW-12 - 200