A good example would be Formula 1 racing. There are other cars that are similar, but they are top of the line..purposely engineered for their one purpose and the 2 meter planes are the same. they change every few years slightly as the patterns change, but they are always at the top of the heap. Also, servo choices make a big difference. Usually when someone is flying a 2 meter plane they are also buying the top of the line servos. Sport digitals are good, but in way do they compare to the quality and precision of the best servos. I saw an example of a guy talking about a 2 meter plane in another thread and I dont remember which one, but after his plane was trimmed, they put a piece of 1" wide masking tape on one wing the plane was trimmed so solidly before that he was able to see that he needed to add opposite aileron to get the plane flying straight again. That is how tight the tolerances are on a well trimmed 2 meter plane...

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