I don't know about Wales, but in the US, satellite is sketchy at best with their service - cloudy skies means you're not getting online. Also, over here, we have download allowances which, at first, don't seem all that bad until you realize how much internet you actually use in your day to day life. I had to surf with images and ads turned off pretty much all the time. If you run out, you either have to buy more or wait till the end of the month and your allowance recharges.
I say read the fine print, just in case!