Oaza on Slovakova street is a hard place to rate. On the one hand this this ideal place to eat when you're poor student and want to be sure that your meal is vegan - food is cheap (cca 1E for meal), hot and marked properly. You can choose between 2-3 soups and 5-7 main dishes. And the food is not bad at all! This is one of very few places which serve buckwheat. The food is trying to pretend traditional meals and their taste. Food is marked with M for milk, V for egg (sorry, Czech word is vejce), S for sugar and L for gluten. That's enough to find the good combination.
But: there is no place to seat - you eat standing. The food isn't made from fresh vegetables - soups contain frozen mixes, base of every meal is quasimeat (soya, tofu, klaso, robi) + typical sauce + rice/buckwheat/knedlik (dumpling). There is salat (mostly cabbage), but with sugar. Nutritionally nothing to be proud of. Spices: sugar, salt and pepper. Around 12-1pm it can be full od people
Maybe now you can see why it's so difficult to rate. It's good but not really healthy. It's average, but not a culinary orgasm. It's finally cheap, which makes this good destination for everyday eating (definitely better than bread and bread).
I would say: in between the price and quality given - Oaza is excellent.
Cons: nowhere to seat, way of preparing food