ive been runnin those since i got back on a bike 2 years ago and no probs at all.
im now at my highest weight ever of 245lbs, and i havent killed my axle yet with those on there.(havent done much rear wheel tho). only prob is that my rear hub weighs over 30 ounces with the adapters on it.
just make sure u take the stock lock nuts off the hub. the axle adapters will substitute for the old locknuts and also wont make ur wheel too wide to fit into the dropouts.