I noticed my tread on my slash appears to be wearing down quickly. I have only had it 2 1/2 months. At what point do you change them. I run it on parking lots at full speed and at the track on 1/2 speed. Also My wife also has a slash 4x4 and her frount rin cracked, Is this common or a result of hitting jumps too hard. Has this happened to others. Last question I got a set of 4 slash tires and rims on ebay for 30 bucks is that a good deal or should i have just bought the tire from a hobby dealer. Any help would be usefull.