Don't really think it's fair to compare the 2800 to the 7000 – totally different hardware, different size, shape etc. I had a Road Angel (7000) – it was crap!
I had a play with the 2800 at the Cycleshow and it does look much better – v fast scrolling, nice screen & quite intuitive if you're used to the memorymap way of doing things. It's supposed to be weatherproof, although not nec completely waterproof (as in dropping it in a river). I'd be a little worried about the touch screen getting hammered with use out in the mud but only time will tell.
My Bro's just received his in the post (having ordered it at the Cycleshow!!) – I'll let you know how he get's on.