I’ve got a Kenwood DAB unit, predecessor to this one:
http://www.halfords.com/sat-nav-audio/car-audio/dab-radios-car-stereos/kenwood-kdc-dab361u-car-stereo-with-digital-radio
For £100 you really can’t go wrong, it’s got a front USB socket, it’s actually on the right of the unit, behind a little clear plastic flap that flips back, the DAB reception around where I live, Chippenham, is generally really good with only the little stick-on windscreen antenna; I’ve driven down to Weston-Super-Mare on the M5 and only lost signal on the elevated section a couple of miles south of Avonmouth.
I lose it from Devizes across to Salisbury, though, but I hardly ever go that way anyway.
Great little unit, simple to use, I’ve had an Alpine unit which had an iPod interface, and it was a pig to use, horribly unintuitive interface, just changing the time on the clock was an exercise in tear-inducing frustration.
Volume up/down buttons are a no-no, a knob is essential.