Agreed. If you are going to be 12-15 feet away I would be thinking about VP150. If the speakers are along the 20 foot wall, a couple of feet into the room, and you are sitting 2-3 feet away from the back wall then you would only be ~7-8 feet from the speakers and the VP100 would be more than enough.

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8