The 'flop'n around' point is a good one, so I guess it may depend on the type of controller you have. Mine is the size of a pack of smokes, and has a plunger type activator... it's easy to simply grab and push the plunger with my index finger while my left hand remains on the wheel and my eyes on the road/rear view mirror. That may not be as easy with the lever style as shown in the pics above.

Cheers... Brian