Just wondering what you guys are using to install an on wall VP150. What hardware. ? Will regular plugs do the trick on gyprock?

I would never use those little plastic plugs. They rip out way to easily. Best is always to get at least one screw into a stud, then use toggle bolts for the rest. They will grab on to a larger area of the drywall/gyprock and prevent it from slipping out, but use the biggest ones that you can that the bolt will still fit through the holes in the mounting bracket.

+1
Or mount a small shelf that the VP can sit on as an alternative? That can give you a bit more flexibility to hit a stud and keep things symmetrical.