I would go with Moser parts any time. They are not some "weenie" aftermarket company. The owners are true racers with multiple cars showing up at Div 3 NHRA races and being VERY competitive. They have very good customer relations and fast turn-around times. I had a car with stock axles at a Thursday Test-n-tune at Indy, and snapped the splines. Called Moser Fri afternoon with specs. Picked up the axles Sat at 8am, had the car racing Saturday night.
I installed a complete Moser 60 in my 71 Charger R/T - 3800# car running 10.00's in NOS. No problems. I installed the Moser rear after twisting the flange off one of the MW axles that came in the used rear end. When I called them with the axle serial number their comment was "well those are old axles and you sure got your use from them. We can have you a new one in 5 days for $375" (1 axle). I also found out Mark Williams splines do not interchange well with other spools or posi's - so I replaced the whole darn thing. After the comments and attitude I got from them I would never purchase anything from them. Doesn't mean they don't have solid parts, but I spend my money with people that treat me like a customer and not an inconvenience.
My new project has a 9" rear with Moser 35-spline gun drilled axles. I will have to get a total weight when I put it together. I am hoping with the fab housing, drilled axles, aluminum center section, and lightweight brakes the whole assembly will reduce the unsprung weight of the car.