Well, I finally got it... a bargain brand new at 330 quids.
Loving having HD finally. My PS3 feels like a brand new console and 2 PC screens is just funky.
A couple of niggles tho (neither of which are deal breakers)
1) Even with the TV switched off, it seems my PC is outputting to the 2nd screen. E.g.. there was a folder on the TV screen last night and I shut everything down. Then this morning, I booted up just my PC screen and double clicked the folder... and it didn't appear.... it was on the turned off screen.
2) Its a bit of an arse having to go into my sound settings and set the default speakers from outputting from the speaker slot, to outputting through HDMI each time I want sound to come out of my TV.
3) My HD 5450 occasionally struggles to run my monitor (1680*1050) and the TV (1920*1080) I noticed that if I'm running a 4gb film then I notice the occasional frame drop, but running 2gb films seems to have no effect.
I'm sure there must be ways around 1 and 2, and an upgrade will sort out number 3. All in all.... AWESOME !!