I've had Boost for a few years now and since day 1 I have never been able to get more than a 1 bar connection of 4g and often no 4g lte connection at all..
Now for the most part this never bothered me as I don't use my phone for gaming, and only occasionally use it for streaming so I usually just switched the network settings to keep it on a 3g connection and the 3g service is mostly acceptable (not great, but acceptable for the price). I am also still using a 4g compatible galaxy s3 so to some extent I have chalked up the lack of a good connection partly to the device being older.
Now I am looking at upgrading my phone to something more modern (possibly a s9) and with that likely increasing my data usage, so an unlimited plan would be likely. But unless I can see proof of Boost being able to provide a stable 4g connection (as it advertises for its network and coverage) I will be taking my business elsewhere.