Seems to be they'd have to be slower for reasons as Steve stated. Of course it could be the increased traction helps the corner drive so much that it negates the higher driveline losses.

I just put a welded diff in my car for the Daytona race. It isn't that I wanted a welded in the car, just that the 3.56 gear I wanted to put in the car is coupled with a welded setup spare diff. Easiest to simply bolt the whole thing in place. I imagine it'll be a pushy car, hope it doesn't have any life threatening handling characteristics.

R