Paul that is a fantastic time for your first marathon.
I done my first in Paris in April this year and done it in 4hr 14 min, for Munich i wasnt expecting as good a time as I really hadnt put in as many miles as when training for Paris, but I managed it in 4hr 16min, so was well pleased with that. I was going good all the way, until about mile 22, then the legs just seem to go and stopping at the drinks station was certainly hard to get going again. coming into the stadium was fantastic.
you are like me then after my first marathon looking for your next one. I got rejected for London for next year, 1st time at applying, but never mind. possibly looking at doing edinburgh marathon - nice and flat so i have heard.
Once again well done on your time, I hope you celebrated with a beer afterwards!!