This may have been covered before but I still read people complaining about the hubs mushrooming out. Anyone who has new wheel hubs might want to consider using a dremel or similar tool to remove some of the material from the inside to help keep them from mushrooming out. I have done this on several of my hubs and it works very well. This should be on the list of required mods for people building any new Xray T1 kit along with beveling the battery slots, etc.
The one on the left has been prepared and the one on the right is stock.