Definitely Yak & Yeti, although I've never been to Tusker House. We really enjoyed our lunch there when we went for my birthday in August. It wasn't very busy, but we still had an ADR. Everything from the appetizers, to our meals, to the dessert was great. I would definitely recommend it!
We have eaten at both and liked Tusker House much more than Yak n Yeti. Yak n Yeti costs more so you get a better return on your meal credits but the food tastes better at Tusker House.