Im a utorrent addict so my monthly download size is somewhere between 10-20 GB
Just go for IDM or Sodetel ? you download every day from 11:00 PM till 7:00 AM around 2.4-2.5 gb that means in 4 days you download up to 10 gb and in 8 days up to 20 gb.
Well i use Rapidshare/Hotfile.... to download my tutorials or movies do the download speed is around 100 kb/s-120 kb/s, i don't know about Torrent download speeds, it depends on the peers and seeds for each torrent.
Edit: I download around 70 gb a month, and i never had a problem except once so they fixed it. I don't think they apply a Fair Policy because they never decreased my download speed.