I don't agree that just because you use a good sub there is no need for towers. Crossover your speakers at 80hz what do you think fills in from there to 2.5-3khz that most tweeters come in at? Yep the other drivers in the box. So more of them make more noise, have more dynamics and more headroom.
I would add to that list the new Boston Acoustic M series which are a BOGO right now. The center is a little pricey though.
As for subs any ID brand sub would be better than a SC2000, 4000, 6000 and even the 8000 if you got $500 or more to spend.
Klipsch RF-62II, RC-500, RS-400, SVS PC12+,
Def Tech SC8000
Harman Kardon AVR 1600
PS3, Apple TV, Sharp 70" Qattron