I've had my Mossberg for probably 17-18 yrs.. I got the Cruiser combo, and I don't remember if I've ever even put the PG on it.
Mine is the 20" barrel with the full length mag. I forget how many "regular" 12ga shells it holds... maybe 8? It holds either 5 or 6 of the 3" OO Buck loads (S&B, I think) that I bought when they were having a sale several years back. These are the long, clear roll crimped loads, and they sort of KICK
I can't imagine firing one with a PG.
Personally, the ONLY reason I could see for having a PG on it would be if I was carrying it in a vehicle, and planned on having to fire it out a window. Can't imagine why I'd be doing that, so the PG stays on the shelf.
The handling, and "pointability" of it is just so much better with the shoulder stock on it. It gives you a reference point for hip shooting, and helps tame the recoil somewhat, by gripping with your strong side elbow while firing.
By the way, my Mossberg has NEVER failed to feed or fire. It's been utterly dependable, even though only I clean it once every year or so (whether it needs it, or not
)
edit: I forgot to add, I even took it pheasant hunting up in Iowa one year.. it was the only shotgun I had at the time. Talk about raising some eyebrows... "you're gonna use a RIOT GUN for pheasant??" funny stuff.
It worked well, as long as the shots weren't beyond about 25-30yds or so.