Welcome aboard and don't worry about your english.
We have english people here that don't speak it very well either.
As for your questions, i recommend you read through
this old thread in which fhw (a member here) posted his thoughts on the very speakers you are interested in.
Personally i find that speakers with three drivers over two gives a better range of sound, however that being said, either the M40 or M50 will be a pleasant speaker if you already like your M3s.
Go with your budget first. Higher cost does not always equate to higher quality and in the case of Axiom speakers, it's all good.
