Hi indyaachen,
if you're based in Aachen, I'm sure you're aware that there's a very good school in EDKA (Aachen-Merzbrück), Westflug with well maintained aircraft.
They can offer you a wide range of aircraft as well, from Katanas to M20Js. I don't remember his name, but apparently one of the FIs there is quite an institution flying Mooneys.
Don't bother too much about lessons getting cancelled due to weather. Yes, it will happen, however you will get used to the environment/weather/procedures you'll be flying in once you got your ticket.
All the best,
Alex