In your situation, any satellite service will be the same. As long as you stay below the FAP threshold, you'll be fine. If you go above, some will throttle your speeds back to dial-up, others will tack on overage charges. Read the FAP conditions thoroughly.
With Starband, I had a rolling 7 day 1Gb limit or about 135Mb per day average. As long as I stayed below 1Gb in any 7 day period, I had good speeds. If I went over, I was throttled until I fell below 750Mb.
Service itself was fine, but they started jacking the prices up later on. I was grandfathered into a program that is no longer offered, so my rate was frozen.
Weather was the biggest issue. Heavy clouds overhead blocked the signal and ice/snow on the dish would do the same.
You might also look into Exede: http://www.exede.com/http://reviews.cnet.com/8301-18438_7-57361444-82/exede-the-satellite-broadband-service-youve-been-waiting-for/
We had Hughes at work when they were DirecWay before we got a wireless local ISP and never really had any major problems.