I recently visited Marburg and had a coffee and bagel here. Being Aussie, I'm quite used to great…read morecoffee and the coffee was quite good without being utterly outstanding; much, much better than the usual chain coffee like Starbucks, not quite as good as Melbourne's boutique coffee makers in Fitzroy. Certainly, the best you will get in Marburg! The bagel was huge, and really tasty, the one I bought was a cheese and egg bagel but I certainly wanted to try some of the others. Staff were also really very nice and were able to understand me despite my mangled Deutsch.
When I move to Marburg in a few months, I will most definitely be visiting here again (probably daily....)