I guess I better qualify my previous messaging even more. When I think of model engine "experts" I also think about the guys that can take pretty much any engine and re-engineer, overhaul, or totally rebuild the thing. For instance, I'm really impressed with the guys that can take a glow engine and convert it to gas. Yes, I can take my engines apart and clean them and lubricate them...etc., but I consider that all just basic maintenance work. Likewise, if I strip out a bolt or need to replace a part w/ a like-for-like part, those are things I have knowledge of. But I know plenty of guys that have been flying RC for years that cannot do those things either. I've seen them get frustrated with their gear and just throw it all in the trash rather than spend a little effort to get things fixed.
What makes some of these engines, e.g. JETT, Rossi, MOKI, NovaRossi...etc. so much better than others? Is it the manufacturing process? Is it the quality of the metals and metal alloys used? Is it the porting, the bearings, the design? All of the above? Evolution engines look really sweet, but I've never read anything really great about them. There was a time when I read that Magnum, Aviastar, ASP, and Thunder Tiger engines were total junk, but on the flipside I've read posts from guys that swear by them.
I love to hear examples from folks that run a given engine for years and state that these engines still run and perform like new....tell me more!! It's the ones that share stories about buying a brand new engine and having it run great out of the box for a couple gallons of fuel and then share horrors of these engines literally falling apart w/ broken rods, shot bearings, rough idling...etc. that really worry me and those are the engines I want to learn enough about to stay away from them. Clearly this means that some engines must be built for short duration high performance, yes/no/maybe?
In the 70's soooo many fliers I was around swore up and down that FOX, ENYA, and K&B were the best of the best of the best, but here and now I read otherwise.