I've just gotten into IPTV, mostly using an Amazon FireTV stick. I have a very helpful suggestion, use a bandwidth monitoring tool on the FireTV Stick. I've found this app: https://www.amazon.com/gp/product/B0786KC4C1/ref=oh_aui_d_detailpage_o01_?ie=UTF8&psc=1
This app will put a bandwidth gauge similar to Netspeedmonitor on Windows ( https://drive.google.com/file/d/1-dg073pT-zUchNRi0KpQQeV6gGlq6Fih/view?usp=sharing ) on the screen for people who need/enjoy the extra information.
And if I'm able to pull at LEAST 600KBps, my streams seem much more reliable. I've seen Netflix reliably pull 5000KBps and the latest provider I've tested was consistently pulling 600KBps at minimum.
Metrics are always helpful in this area. More bandwidth BURST, less buffering.
EDIT: For Android, try : https://apkpure.com/network-monitor-mini/info.kfsoft.android.TrafficIndicator
that won't tell you anything that looking at the tv screen doesnt tell you already, you dont need to monitor current bandwidth usage to see something freeze, stutter or start buffering! What it MIGHT help tell you is what kind of bitrate the streams are using vs another provider, if one provider is consistently at 5mb and another is 3mb at the same time on the same channel then chances are the 3mb provider has a lower quality stream.
bandwidth use is also going to go up and down drastically depending on what is being displayed, especially if using HLS which can use 12mb one second then 1mb the next as it grabs the chunks. So monitoring bandwidth will tell you nothing about how reliable it is going to be, but it ight give some clues as to whether it is a higher quality than another provider (and even this you can probably tell just by looking at the tv).