Hard to say, actually. I've had three of these, and one had a defective weld at the canister/downtube junction, which is where I beleive most problems are occuring.
Bob at DLUSA replaced mine quickly. Another developed a very small leak, and after cleaning and putting a small bead of JB weld on it, it resolved.

Tough to say; but I wouldn't let the 'odds' dissuade me from buying. They are good engines and represent good values, I think.