If you can stretch a bit more the SatMap Active 10 with all UK 1:50K maps included is on offer to LDWA members at £265 !
If you don't need the 1:50K maps, it is £225 including extra battery, but for £40 it would be daft not to take it (IMHO !)
Bike mount would add another £20 (they also give 40% discount to members).
I haven't yet got mine, but the deal was fantastic value (of course I spent even more on a few maps, etc) and I have a hiking mate who *highly* recommends it !
http://www.ldwa.org.uk/2012Hundred/W/1838/gps-offer.html for details.
cheers
Mike