I'm not a fan of Dixons, never have been, but if you have access to the YouAtWork facility, you can get some decent deals. Current web price for the 434 is £3799, but with YouAtWork you get another 7.5% off that (£3514). Not sure about delivery charges.
It's a web based discount scheme that some corporates offer to their staff. There is a registration and logon process. I work for Vodafone and we were given access to it, but I'm pretty sure it's not Vodafone specific. It then links to various web-sites including Dixons, Dabs, etc.
How it works when you get to the point of purchase seems to vary. For Dabs, you can only order over the phone. For Dixons I suspect it may automatically enter a voucher code. It looks a bit like some of the CD-Wow voucher schemes.