The 100GB storage thing does seem a bit bogus. Maybe it's to tempt you to put all your warez on there. Whetever you fill that space with, you're only going to be able to look at it once a month before you go over your bandwidth quota.

Then again, if you're moving sites, you know exactly how much storage and bandwidth you need, and how you expect it to grow. I would have thought any site would have far greater bandwidth requirements than storage requirements. Maybe I've missed something. Anyone?

All my sites, code and data, including some development work that's not yet online, totals less than half a gigabyte. It's a good month if there's more than 1 or 2GB of traffic (we have no heavyweight content) on my server. One thing that might subtract from that is backups - I don't do backups over a network, they happen on the server, so that saves about 6GB of traffic a month. And that's compressed data (which would cost either CPU on the server or double bandwidth to compress at home). Oh! Maybe that's worth considering. Do people with webhosts do their own backups? Or is that part of most hosting packages?