Nitro/progo sucks. I found I had more luck with ts.

Hls can allow your stream to change between quality settings based on your connection. However, it seems to time out for 30 seconds or so after changing channels, so if you like to go back and forth between channels it can be a issue. Also, I don't know if it provider specific, but when I tested it with my last provider, it caused issues if 2 players in my house tried to steam the same channel (even tho I have 5 connections). For this reason, I stayed with ts streams. I would only use hls if I was on a slower connection and getting a lot of buffering.

Others might be able to offer more insight, but that was my experience.

welp, i have ultv336 its buffing bad too. The 49ers vs Packers keeps freezing and the wwe ppv keeps buffing and repeating itself.. didn't realize how good i had it when gearz was up and running. There is not even a 2nd close

Delivery of IPTV comes in 2 standards MPEGTS and HLS . In essence both function the same way (video is being split into small mpeg/ts chunks. While one chunk is being displayed, another one is being downloaded).
However... There is one big difference between the 2 standards.

MPEGTS is the older, widely supported format which is not aware of the network conditions.
That means it sends video chunks at a standard rate no matter the speed/condition of the internet.

HLS on the other hand is the newer standard, developed by Apple. Not yet 100% supported by all programs/devices. This standard is aware of the network speed/congestion. That means it can sense and switch the resolution of the video "on the fly", depending on the network conditions.

Keep in mind, MPEGTS (in this case the " ts " format), gives you the full quality, no matter your network conditions.