If you're flying the big twins (or anything 40cc or bigger), I'd seriously look at the Model 4.

I have one. I got it because the first guy I met at my new club had nine fingers and three hundred stitches in what was left, courtesy of a DA 100.

It simply rocks. The nine finger guy has used it on his DA 100, I start my US 41 "like it has no piston". It has a cup well designed by Miller RC to grip 'any' size hub or spinner. (reversible)

I run 24 volts, from two 535 amp car batteries. I can let everyone use it and not have juice issues. I rewired it with a pair of jumper cables and terminal clamps. I just leave it in a pilot box, and whoever needs it can fly out of that box.

It cost me three hundred bucks as pictured. Batteries are cheaper big than small!. Heavy but lots of juice, and just set it up and leave it for the day. Sure, hook up that charger, too. No problem.