@zeeya bro, please see below.
1. Is it worth over my existing box (not in terms of money) ? Except for giving the flexibility of OTT/DTH in one box, there is no real advantage of this box over your existing Android box. In fact, you will miss recording feature (Not enabled yet), original audio due to fake Dolby Digital Plus on all the content and favorites feature.
2. How about the favorite channels setting? There is no favorite navigation on the remote for this box. The only thing we can do is, add channels as favorites which in turn would show all of them under "My channels" on the home screen. No way to navigate the way we do on a regular HD box.
3. Can I go back to my existing box if I ever didn't like it? I think we can, but you might have to fight with the ADTV customer care for getting a refund into your account.
4. AQ & PQ? AQ is very bad, because they are pretending Dolby Digital Plus audio on all the content (Even stereo), but are muting 3 channels i.e. center and surrounds! This will affect the AQ severely, especially if you use a home theater. PQ is excellent though!
5. Channels navigation ease. - There was a freezing issue, which seems to have been fixed with the latest update. This is good now.
6. Channel search using Google Assistant or Voice. - It's a hit and miss. It stops working all of a sudden and we need to pair the remote again in order to make the Google Assistant work. But it works fine after re-pairing!
Let me know if you need further info.