I would give the brunch 4 stars because it is a fun place to go--I like the atmosphere, the diversity of the ALL VEG offerings, and you can't beat the $10 price. I was not *amazed* by anything I ate there, and the service was sometimes a bit sketchy, but it was all good enough and the options and affordability make it some place to which I will return on Sundays to come.
Dinner, however, was another story. My girlfriend and I stopped in for an early dinner on our way out to a free concert in South Park. We ordered grape leaves (6/$3.50) for an appetizer and we both had the Tunisian Red Bean Stew (red beans, yams, red peppers, tomatoes, onions and jalapenos simmered in a spicy peanut sauce over rice), served with a side salad ($10).
The grape leaves were quite good and easily the best part of the meal. The salad was downright bad. It was all the same kind of lettuce, smashed into a bowl with ~4 pieces of green bean, about the same number of red cabbage shreds, piled with bell pepper (which I hate), and a few grapes. The dressing was so strong with vinegar it made us both cough. There was so much pooled in the bottom of the bowl that we just left the bottom third of the salad because it was completely inedible.
The entree was okay, but not wonderful. It was a little dry, the elements seemed to blend into each other rather than stand out individually and the sauce was one-dimensional. I usually expect a "spicy peanut sauce" to be a little more complex with the peanuts adding a sweet-savory base on which the heat from the peppers can play, but the pepper heat washed out the peanut flavor in this dish. The rice managed to be both sticky and dry, so the meal felt pretty heavy.
Despite the criticisms above, Zenith is okay and it certainly is not overpriced. It is a fun place to dine as you'll always find some new funky object to check out, but don't go expecting to be amazed by the food. There are more options available for Sunday brunch and you can't beat the all-you-can-eat sides and sweets.
It's worth going for the Steelers shrine alone.