No doubt they are an excellent mower however, comparing the specs on the Big Dog Diablo MP vs. the comparable Hustler Super Z with the same engine, there is some minor differences such as the Super Z is longer in length and weighs more. The deck is also a different deck as the Diablo 60 inch deck takes 21 inch blades and the Super Z takes 20.5 inch blades for the 60 inch VX4 deck. I can only assume there may be some minor difference in the smaller mowers as well. Both are exceptionally well built with only a minor differences. I would not hesitate to buy either one. Also compare the warranties as there is also a difference in them. The Big Dog 7 year warranty does not cover all the parts such in the power train for 7 years and the after 3 years only parts are covered from what I see on their web site. I did check them out close before making my last purchase but my main reason for selecting the Hustler that I wanted the best commercial mower in my opinion I could buy which is the Hustler Super Z HD and which Big Dog does not have one to compete and having faith in the dealer who carried the Hustler brand. However, I will admit I probably bought more mower than I really needed with the Super Z HD when the regular Super Z would be more than adequate and which the Diablo compares with very favorably.