I am using Tata Sky for more than 1.5 yrs now. In the beginning I got installation etc done with-in 2 days.
I had problem once with the dish alignment, it got fixed with-in 24 Hrs. Experience with customer rep was good and my call was picked up very quickly as well.
Recharge was an issue in the beginning but now I pay through tatasky website. It is very easy. TATA SKY browsing is user friendly. I have tried DISH TV at my friends place, it was difficult.
Picture quality is same in both. Number of channels offered by DISH TV is more than TATA SKY for Rs. 300 per month package. Based on the reviews at mouthshut, it seems my decision for TATA SKY was right.
During heavy rains, we have experienced signal loss for few seconds but that doesnt seem to be an issue. I am sure same problem exists with DISH TV as well.