Downloading "...intermittently...."?
Whats are your speed results from Ookla?
What is your router and did u connect to 5 GHz, ethernet?
I have ToT and just tested to all corners of the globe using ookla on 5GHz wifi, macOS, both latency and speeds are all very good: nothing less than 700Mbps from Thailand to servers located on US west coast (SEA), east coast, Canada, EU (Germany) Ukraine (Kyiv). AU; Perth, Darwin, etc.
I find ToT is reliable and provides consistent high speed connections overseas to USA and the other way to the European servers. Maybe u have a bottlekneck in your current network system including your computer, router, settings. All need to be tweeked for max performance. I seldom have a slow connection from Thailand to local servers and international connections, always have great speeds.
I am not an IT expert by any means but take network advise from wherever I can get it as needed.