I tried Tana a few weeks ago and I'm jonesing to go back. We had the Tana sampler and it is definately the way to go if you want a variety of dishes without hurting your wallet.
The sampler is served on a flat bread that is also your utensil, enjoy eating with your hands.. I did. :)
The toppings can be either meat or vegetable dishes. I recommend the Yesega Wot in Kay Wot sauce. It is only a little spicy but very flavorful.
One thing is that the server did mess up our order. My wife and I both ordered the sampler, and we did get everything we asked for - but only between the two of us. I had some of her choices on my dish and she had some of mine on hers.
One particular note: I asked if they had Kitfo on the menu. They don't, but with 24 hours advanced notice they are willing to make it! Next time...