I think a lot of people make the mistake of thinking that "hassle-free" means "no adjustment." Any model engine of any brand is going to require adjustment from day to day, and even sometimes from flight to flight on the same day. Atmospheric conditions (temperature, air density, humidity, etc.) will affect how the engine runs. In many cases, as theengine heats up after a flight or two, it may require some additional tweaking to keep it running right. Also, some of the problems you guys are describing sound like a possible air leak somewhere int he system (carb? fuel line? muffler?). The most insidious one i've experienced, which baffled me for some time because the engine was cowled, was a razor thin cut in the fuel feed line right at the copper tube coming out of the tank. I thought the fuel leak I was seeing coming out of the cowl was from the muffler coupling being loose so I kept trying to tighten it, but never noticed the cut fuel line until the engine quit on me on short final. The leaking fuel had weakened the wood at the landing gear mount, and....*poof*....off came the gear on a fairly normal landing. Fixed both the fuel leak and the gear and she's now flying again. By the way...this is an Evo 46NT I'm talking about. Also have a .455 trainer engine I'm waiting to put into another plane soon. I like the Evo's so far (and yes, i removed the h/s restrictor right away!). Good luck with yours!