I don't think any of them are quite 'there' yet. I used an Etrex Vista HCx on my tour last year, and I'd say that the interface is really clumsy, the screen too small to be really useful, the vector graphics are completely rubbish, and the thing kept locking up when it lost satellite signal in the mountains. And it's pretty battery-hungry too, even with Lithium Energizers, making it not a great choice for a multi-week tour.

There's a device available in the UK called 'Satmap Active 10' which looks a lot more useful, because it has a fairly large screen and uses scrolling bitmap Ordnance Survey maps instead of Garmin's vector graphics. Maybe something similar is available over there?