That didn't look big enough for that size of screen, which is why I thought there would be room under it.

Ya, the FMB will hold the VP150 but use caution. The VP150 has a threaded insert in the back of the speaker that the FMB simply bolts to. There have been a few reports of the VP150 twisting on that lone single bolt, so I would add an extra screw or two through the outer openings on the FMB mounting plate. There was another instance of the insert pulling right out of the back of the 150, the solution was to drill right through the back of the speaker and use a nut and bolt to hold the FMB to the speaker.


Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70