I've been looking at FoodSavers recently so I just called them up to ask about this. The only one that sucks harder is the top of the line
Gamesaver Turbo Plus ($299). It's the only model with a double piston pump.
Other than that, some models have 2 vacuum speeds, but that only changes the speed of the sucking, not the strength.
In case anybody's looking at buying one soon, I was also told that the
V2830 kit (I think that's the one she was talking about) is a lower price if you order it direct from them, but I'm seeing it for the same price ($99) elsewhere online so maybe I misunderstood. The rep did say that you could save another 10% if you call and place the order versus ordering online from their site. I'm not sure how their direct prices compare to someplace like Sam's, but they seem to be the same as Target.