Since the Xbox One is region free, players are free to consider import options, with the UK exchange rate occasionally working in our favour. Play-Asia are currently offering a tempting £38.72 price for two of the most intriguing Xbox One exclusives - Titanfall and Quantum Break - which will net you a fully compatible US copy.
However, before you take the plunge, I must point out that Play-Asia can be notoriously unreliable when it comes to timely shipping. I've personally had pre-orders arrive several days (if not a week or more) after launch due to the worldwide shipping and customs, so approach with caution. Zavvi aren't always much better, but they might be a more reliable source for Titanfall with their WANTED10 voucher code.