Peter was a great host: very accommodating and communication was easy/good, which proved to be very important because coming by train from Strasbourg via Stuttgart we were delayed and thought we were going to miss our connection which would have meant arriving 1 hour later (at least). In fact we made the connection (just!)
The flat was easy to find and well located. Only 2 stops on the Ubahn from Hauptbahnhof - we contemplated walking (even with 3 children and 5 big wheeled bags) but it was VERY hot and transport was cheap and easy: there were even lifts up from the platform to the station and then to street level at the nearest station. Munich buses/trams/trains are very user friendly (get the transport map/booklet from a ticket office: it has various maps and lists the sights and how to get to them). We always got 1 x Inneraum ticket for 5 people (Euros 11.70 available from all machines) validated it once before boarding our first ride and were good to go anywhere in the inner zone until 6 am the next morning! So getting to see the sights could not have been easier. And very nearby there were 2 supermarkets (ALDI and Edeka), a coffee shop, chemist, restaurants, 2 Beer gardens ;-) plus the Transport Section of the Deutsches Museum which is well worth a visit.
So all in all the flat was ideal for the 5 of us (2 adults, 3 kids aged 13, 13 and 11): spacious and full of natural light from the skylight windows, and well equipped too with everything we needed.
We thoroughly enjoyed our time in Munich and the flat.