I bought one of these engines and installed it in my 76 inch Extra. Have not flown or even started it yet but 2 guys at my field have the same engine and I noticed that both DLs really run very rough, lots of misses, especially in the midrange. Both engines were not tuned and were flown with needles untouched from the factory. Granted the engines have basically 1 hour of runtime. I wonder if it's normal for a DL to miss so much in the early stages. My CRRC PRO GF26i run flawlessly from the get go until it quit, a gallon later, but that's another story.