Definitely get the VP160 I've had mine for a couple years totally awesome unit. With the 600 it's possible the M22 are sufficient as the 600 will do it's job beyond well. though for the size of your room you may want to take advantage your room boundaries that's quite a bit of space to pressurize.

The 160 will also really help with low end, running mine through an Axiom ADA1250 set to 40Hz. Man can it thump with ease.