No problem.

Please don't forget the obvious advantage of having multi-room: You can see all the same channels that you subscribe to on your main STB.

As it is for the spare room though, I couldn't justify spending money on the top of the range STB. There are plenty of cheaper ones available.

If you subscribe to Which?, take a look at their website. They did a comparative study on various STBs a few months ago. SD boxes without a hard drive start at under 50. Be prepared to pay from around 100 for a STB with a built in drive.