Lets see a game in the US costs $49.99. Shipping to the UK would be around $15.99 (
reference). So that comes to $65.98 in US.
Based upon the exchange rate (
1 USD = 0.509591 GBP) that would be 33.6228 GBP.
According to
this UK game store (not sure if it is a main one or not), the same game would cost 39.99 GBP.
So he would save 6.3672 GBP or $12.49 in US dollars.
I suppose thats worth it unless there are any import fees that I am unaware of, but I'd hate to be waiting a week or two for a game to get to me.