Echtzeit is a nice option if you want to go out with some non-vegetarian, and non-vegan friends, because everyone will find something. The menu is quite mediterranean with pizza (baked on a stone), pasta, salad, grilled vegetables, ...
There's a bar with bread, and baskets--you can fill, and refill the latter as often as you want. But keep in mind, that some of the bread types may not be vegan, because the bakery Cibaria, where they come from, uses enzymes on the basis of honey. It is not clearly marked, so better ask the staff.
And I cannot recommend the yeast sauce on the pizza, just eat it without cheese. Imagine biting into a cube of yeast...not THAT yummy! But the salad is great, really try the "Mirabellen Dressing"!
Cons: bread not clearly marked as vegan, staff is sometimes hectic, lamps on the tables are dusty