They offer much lower resistance than your standard mini connectors (i've heard up to 15%).
The drawbacks are that you have to:
1) Convert your batteries to dean connectors (make sure the female ends are on the battery *cough Spa*)
2) Make a dean connector charger wire
3) Convert the rest of the wiring harness to dean connectors (on a g36 I think this comes out too needing 3 male+female connectors; 1 at the gearbox, and 2 at both ends of the fuse-wire piece)
For all of this you're looking at 4 male/female dean connectors. I'd definately say its worth the soldering
The biggest thing of all to keep in mind is that you MUST have your batteries charged at ops, or you'll have a real hard time finding someone to borrow a battery off of