Welcome to Axiom. The vertical M22s are more suitable for use as main speakers than are the VP150s. If the horizontal configuration of the VP150 isn't an essential factor in an installation, there's no good reason for attempting to make use of them for mains.
As to whether to use in-walls or the hybrid in-on wall version, although your sub will be handling the low bass, the in-on wall version may have an edge in the mid-bass and should be slightly preferred.
Note that the in-on wall M22s are presently on a 20% off clearance sale, with supplies limited.
