I have both Dish TV (for last 4 years)and Tata Sky (for last 1 year)at home. I think I am better positioned to answer this. I will give comparison and you are the best judge. for me it’s just other side of the coin.
Dish TV: Excellent picture quality (when works), real Sterophonic sound, works fine if there is no cloud or rain. So long you are getting channels you are in heaven. The moment channel problem occurs your life sucks. 90 minutes to get the customer support connection (1860 180 3474), if you get connection enjoy for another 40 - 90 minutes for hearing " your call is important to us... etc.
If still you have patience or on speaker phone, some lousy wrong english spoke fellow will say hello, asking about your all details, asking apology for your problem will note down the complaint and will give you the complaint number. Thats it forget after this and next day repeat the same process....and it goes ever. renewal can be made through credit card on website. but never attempt to change your phone or email ID in profile, it will not work. keep knowledge about how to complaint in consumer court, you may often need it. if you are holding old set top box of "ZENEGA" make your position may be slightly better.
Tata Sky; picture quality not digital, Sound not stereophonic, much less number of channel than Dish TV, musch costlier subscription fee than Dish TV, works on moderate rain but on heavy rains god forbid. Do not get tempted with active menu, never try it. if happens accidentally, no channels will come. Switch off the Set top box from plug point, remove the subscriber card, rub it on your back re-insert it. Switch on .... Eureka it works. Subscription renewal can happen through web site. didn’t have chance to call customer support yet - hence no experience with customer support. Now you decide which one to buy.