XStream didn't have this when Airtel introduced the box. One didn't need to have an active DTH plan to access the OTT content. They have later changed it and updated the software to check for an active DTH connection. TS is not asking for an active Binge subscription today, who knows, tomorrow they might! Owning the device means you should own it without a need to spend a monthly amount on it. If someone wants to watch only free OTT content there shouldn't a need to spend anything.
What I'm trying to say is that, if OTT is the preference for the OP, the hybrid box won't serve the purpose as it requires a mandatory monthly installment. On the other hand, if OP is looking for DTH+OTT, then the hybrid box is the way to go.
1. Amazon prime app doesn't have Dolby 5.1 on XStream and Binge boxes. It's a known issue.
2. Dolby True HD, DTS HD, and DTS:X formats are not supported on XStream and Binge boxes. But these can be experienced only with an advanced Home Theater system.
4. He is saying that all apps are not available on the Play Store of the hybrid boxes whereas, on the MI Box, they will all be available.