I will write this in English to help tourists and international visitors who would likely need some…read morehelp while in Munich-
Out of the major photo-specific and big-box electronics shops in Munich, this is the one I would recommend not only to residents, but to visitors. The store is not large, but is densely packed with inventory and part of a chain that can order what they don't have in stock in a short time. They carry numerous high-end lenses and bodies, so pros and prosumers won't be left out. At least one representative speaks English fluently (though I use my German when there).
Prices: their prices are often, by a large margin, THE best around, sometimes even beating online sales by a good margin, but most certainly beating Sauter by a HUGE amount. In fact, in the sales I have completed with them, or almost completed, the last lens was 100EUR less than the locals and below online sellers, a new lens from Tamron was only 70EUR more than the used price (I ended up with the used lens because I needed it ASAP).
The big plus about them is that, unlike Sauter, one is not assaulted with extremely aggressive, high-pressure tactics to buy items. Help is given, and unlike the other place, respect. Every time I go to Sauter, I am greeted with a bizarre combination of employees, likely the long-termers, who won't look me in the eye, look bothered to do such things as ring me up for items at the Kasse, LITERALLY shove just-purchased items at me and won't put them in bags before they walk away, and youths in training who are overly-aggressive about sales and trying to make a good showing so they may be asked to stay on. I never see them twice. Gregor has always treated me well, despite being a foreigner.
Sure, Sauter has a good collection of accessories, but Gregor has a very good collection of lenses and bodies in stock. Plus they actually are knowledgeable as opposed to many people at Sauter who constantly fake their way through answers.
Marienplatz also has a photo shop which I recommend foreigners away from, as they tried to rip me off on a 529EUR lens, which they marked up to double, then asked me after I balked if I am a tourist or live in Munich. When I mentioned the latter, they realized they made the wrong call and I realized it was a tourist ripoff operation.
I bought a lens from Gregor which had a problem a couple weeks later. They expedited the shipping back to Sigma and got it back to me roughly ten days later. Awesome service. Nothing out of pocket.
Conclusion: respectful, knowledgeable service, no high-pressure sales tactics, good inventory for pros and enthusiasts, along with knowledge of pro-level equipment, and the best prices in Munich that often beat online sales.