RE: Good .40-.50 engine
ASP .52 is a nice engine. I own one of those, too, except here in the U.S. they're known as the Magnum XLS .52A
The only problem is, at 500 grams including muffler, the ASP .52 is eleven grams heavier than the O.S. .46 AX, which is too heavy!
We need a lighter weight engine here, folks.