The longer handle will give you more leverage if you're shoulder can tolerate the larger turning circle. I don't use my trailer often but the 2 speed really helps alot particularly at the shallow ramp that I like to use. (Close to home)..
You'll find some folks that do feed 5 gals of anti-freeze thru the muffs at idle and get away with it but it's not fool proof. If the thermostat doesn't open you will have a busted engine but your manifolds will still be ok to use on your next new engine...
I feel your pain as my engine is...