The point of using TestMy is to get a speed reference to a known entity, using a known protocol.
Your speed anywhere else on the internet will depend upon the path you're routed through and the server you connect to and may not be the same thing.
You should know that there are problems trying to download anything that's behind certain servers, such as Akamai, which Microsoft uses. Those have been severely throttled and gap-ridden either by Akamai themselves, or someone in the path.
If you specifiy where you're trying to download that's giving you a problem and what beam you're using, perhaps the HN techs can investigate. However, "a 25 Mb file" isn't going to be specific enough for them to do that.
Thanks for posting and sharing your testmy.net results URL. I just ran diagnostics on your site and that's also showing that the HughesNet equipment is working normally. Which site(s) is loading slowly for you?
Your cooperation, patience, and understanding are much appreciated.
Depending on the issue, speed tests can give a lot of info. In your case, speed tests are simply the first step in the troubleshooting process, which is a process of elimination.
Your speeds look good, and apparently there's nothing wrong with the equipment, so this may be related to what Mark discusses in his post. Could also be related to how many devices you have connected, or how many people are using your system at the same time. In any case, I hope this gets resolved for you, as I know how frutrating this kind of thing is.
A couple of suggestions....
The first is to get a snapshot of what you're seeing when a particular website times out. The second is to install a load timer for the websites. "Page load time" is a good one for Chrome. I used it when I had a problem with Facebook taking minutes to load, while everything else was fine. It will show how long it's taking web pages to complete opening, as well as specific elements of that time, and you can take a snapshot of that, too. If and when you do, it'd be a good idea to get the system clock in the snapshot, as well.