Shanti Sagar at CMH is the worst place to eat in terms of value for money. They have 2 division one AC and one Non AC. The Non AC one should be cheaper - but the cheapest thali you will get there is 70 Rs for a mini meal and 100+ for a full meal. It used to be cheap but they increased their rates as the bangalore house owners are increasing rate for the rent. I went there with one of my friend and asked for an orange juice at Non AC place without seeing the menu. And when the bill came it was 40 Rs with nothing special in that - just the normal serving and the juice is also a water mixed juice.
Then I saw the menu and the cheapest thing I found out to eat is just normal break with vegetables which they call - veg sandwich - which is also 25 bucks. So I am suggesting you, go to any place nearby - there are a lot of new places popping around. Other good places nearby are - Asiana, and Mast kalandar. They just started and a good place to eat in comparison to shanti sagar.