Before there were Haisley and SCS axles we ran some Moser 35 spline because they were supposed to be better. In actuality they were JUNK and wouldn't even last as long as stock axles.
My 80 has moser shafts in it, been in there for about 5-6 years now. Axle came out of a much higher powered truck than mine and did not have problems with the shafts.
Knock on wood... no problems with mine yet. My stockers lasted about 10-15 hooks and the mosers have 2-3 right now. We'll see how they handle the 2.6 class if I ever get the p-pump swap done. They told me I won't break them... I find that confidence funny though lol