they are all good engines,some have more stringent quality control,tighter tolerances and better materials but the key to longevity is the person behind the radio,tuning and maintanance.
as far as the go-rods i use them in all my older novarossi engines with excellent sucess and without failurs and i will continue to use them.
i even break-in my new novarossi mills with a go-rod and after a gallon i put the new r7 rod back in
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