I`ve had my Mayhem Pro since last summer. Put a SH .21 6 port in it. This is the best buggy / engine combo I`ve done and seen. The only thing I`ve had a problem with is the clutch shoes it came with. Weak material, I put in Ofna aluminum shoes and has been great. The wing mount tends to come loose , but other than that it is pretty much race ready out of the box. I race it every weekend against Mugens , ofnas and xray buggies . [8D]