Welcome! well I can't comment on the M100's as I've never heard them...I have had a few different Axiom setups through the years..starting with an M60 setup and later upgraded to my current M80 setup. I used 2 different versions of the VP150 and I thought it always sounded just fine with my M60s and M80's. They have had different versions through the years and made changes to the crossovers, drivers, etc...
Maybe someone else will chime in, but I'm guessing the latest version of the 150 should do just fine for movie dialog and center duties.
