I have a shutter release and have had quite a bit of success with lightning shots here in the UK so i'm not sure really. All i'm worreid about is missing the action cause i'm so worried about getting good lightning shots with a shutter release and the worry of CG strikes whilst I am holding a shutter release. You have the safety of being in a vehicle while the lightning trigger does all the work for you don't you?
I'm basically thinking that if I can get some decent lightning grabs here (as I already have) then i'm sure I can in the states as the amount of strikes per minute just don't compare to the poofy storms we get here!