A lot of people like the Humax 9200, costs around �170 which isn't a bad price. It has twin tuners which is what you should look for in any PVR. It means you can record 1 Freeview channel and still watch another, or record 2 Freeview channels and watch the analogue tv channels (or watch a previous recording) and has 160GB hard drive, thats about 100 hours of tv.
We've just come back from holiday in Wales and took ours away with us as the other half likes watching Big Bro and S4C puts it on really late at night. Buy on and you won't regret it. For more info look here for Freeview coverage
http://www.dtg.org.uk/retailer/coverage.html
and here for other DTT boxes and tvs
http://www.freeview.co.uk/products
and here for a comparison of other twin tuner PVRs
http://www.pvrjunction.co.uk/compare/
and theres more
http://www.pvruk.co.uk/