I did a bit more research on this, using different terms, and I think I've managed to answer the question myself - or at least, part of it. It looks like WoW uses up to 30MB/hour, so 2GB should give him up to 60 hours/month. That's only 2 hours/day, which won't be enough, I don't think. But, in my travels, I think I found mobile broadband packages that offer 5GB and more. However, I'd still appreciate anyone's input on using 3G for gaming, how well it works, what the better/worse providers are and so on.