ORIGINAL: opjose
I've used several different sized Evolution engines...
Synopsis:
1.00NX = Worst engine I've ever owned. Dead sticks, deadsticks, deadsticks...
That is bad luck for you, but once the engine is tuned right it should be OK they are a pain to tune though. I have had good luck with my EVO engines including the 1.00NX mounted inverted.
Laurence if you plan on buying the P-51 I would go with the Saito 150 or 180 though it will sound great with that four stroke and have more than enough power.