TomTom Start or Start 2 have the latest maps except the new range of TomToms but i hear they are crap.
You can get the starts on Argos/Tesco Ebay Outlets (refurb open boxed) for a whack cheaper than new.
The maps on the Start 2 were up to date ish, i've never paid to have the maps upgraded as i feel its a load of crap, if you buy a new satnav like i did twice you expect it to have the latest maps, this time around i bought an XL IQ routes refurb from TomTom direct and its worse (Older maps and doesn't pick up all the cameras), even after moaning at them and getting a map update it was crap so stick to the later generation Start range.
http://www.ebay.co.uk/itm/TOMTOM-START-2-UK-ROI-AND-EUROPE-GPS-SAT-NAV-/330571310131?pt=UK_AudioTVElectronics_GPSSystems_GPSSystems&hash=item4cf795e433You could try a Garmin but they are even worse, unless you like driving down single track a lot.
PS. I use my step fathers old Tom Tom One and that picks everything up and has good maps, its a bit random tbh, its like they just decided to put older maps on the newer products, doesn't make sense.