You can have the best polishers money can buy, but if you do not have a good system in place to work with that tool then your not going to get good results, The difference from a quality polisher and a low end polisher is going to be in the amount of passes need to make before removing defects in the finish. A harbor freight require 3-4 cycles before achieve the defect removal your looking to reach before finishing to where a quality machine would only take 3 passes and 1 cycle.