We have Hughes.net satellite and even though the upgraded service is much better than the old there is still some latency. The ROKU works great on it. Even the live streaming news shows work without buffering. The Firestick not so good.
My only problem is teaching my 82 year old husband something new. LOL Once he learns it he does great but his short term memory loss takes a lot of repetition to get some things to stick. Our cable bill is $202 a month and that’s crazy. There are only 11 shows I watch on it and about the same for him. We don’t watch gay shows, Spanish shows, black shows, or cartoons so a lot of our package is a waste of money. If he gets comfortable with ROKU I will cut off the cable and subscribe to anything he wants but doesn’t get free. That will save us about $150 or more a month.
If there was a solution to get local channels/networks other than off the air, I'd pack in cable in a heartbeat and subscribe to a half dozen $5.99/month networks.
Is your ROKU a little box, or is is also a stick? I have only used a ROKU box or an Apple TV box for streaming. I do not think the sticks have enough memory, hence the buffering issues. Also, I connect my ROKU and Apple TV to my router via LAN cables. I mainly use the Apple TV for streaming because I have a lot of iTunes movies that I watch on it.