+1 for Satmap if you want an intuitive, Ordnance Survey mapping GPS. I haven’t used the latest one, but the Satmap 12 stomps all over Garmin in terms of usability and also the quality of map reproduction.
One of the reasons OS map GPS units cost more is that Ordnance Survey mapping – a sort of semi-government / semi-commercial quango agency – is expensive to buy. And you have to buy the same maps in different formats for different apps and GPS brands, but that’s something else again.
Finally, the drawback of OS mapping relative to a simple thing with arrows is that it’s hard to use on the move, it’s just difficult to read a map of any sort while riding. Sometimes that’s a minor thing, at others it’s slightly irksome. Depends on the route you’re following.