Ok another update:
I ran my first full batt pack outdoors tonight. It's a lot of fun and a little violent.

Even with a set of 40 series Big Joes it will lift the front end at any speed. I need to dial down the brakes because at 60% I still can't use them. The truck just goes into a front flip as soon as I touch the brake. I also need to dial down the punch to make it more driveable. I could always gear it up but the top end is hairy enough.
Everything worked great until the truck stopped and I heard what sounded like a blown spur gear and smelled burning rubber. The stock savage clutch melted.
It's a good start!