The "handles" on these rulers appear to aid longarmers, but would, IMO, be in the way when FMQ because you need both hands to guide the quilt sandwich and would lose that leverage using the handles. I've never used this brand ruler, however.
As for gripping on rulers, I use HandiQuilter's HandiGrip tape, cut to size, as it's the best product on the market, that I've tried, for gripping the quilt sandwich. You need something that grips really well, without necessitating firm pressure downward that would cause drag. Additionally, because it's semi-transparent, I can still use the lines etched into my rulers.