One of my riding mates sold me a pair of wheels- 3 months old (near-new) Alexx I think they're called. The hub on the rear has notches on the splines, square cross section notches. He was unaware they were there but apparently had no trouble removing his cluster, however... some of the notches have raised edges, the LBS said "never seen that before" and we cant source a replacement free-hub...shimano cant help... has anyone seen that sort of damage? I cant attach a photo...