Original set up seems important. I’m terrible about not reading instructions, this product is probably the exception to that rule. Spot lock and a momentary switch problem (easy fix on that one) seem to be the most frequently mentioned issues. Some have also had a problem when tracking with hooking a 90 degree turn and going to 100% power, bit more dangerous if standing up. Watch for stumps, friend already has two of those $400+ repair jobs invested in his.