How much is 5gb usage

It's definitely not a good deal. But I'll assume you're considering it because there's no other options that offer unlimited usage in your area. If you're going to be downloading a lot of music or large files (such as movies) then you can use up 5 GB in a hurry. If all you'll be doing is browsing the internet for an hour or two a day then you should be fine. I wouldn't want to sign a contract with them, and watch your usage closely the first month or so because I bet their charges for over usage ain't cheap.