although I'm leaning towards the Dakota, the fact that I've seen a few posts about problems reading the screen in sunlight is putting me off.
They are all difficult to read in sunlight - especially low sun ahead, ie riding east in the morning or west in the evening.
I do think the touchscreen makes it a bit worse - but it's only like the difference between 'very difficult' and 'very very difficult' and it is only in those particular situations. It's basically a reduction in contrast - whites go light grey and blacks go, er, mid grey, and all the other 60,000 colours fit in between. NB these things are not iPhones!! The backlight can help a bit, but is a battery hit.
[edit to add pic - (old) Etrex vs Dakota, in sunlight - this is about as good as it gets ...
Having had a Dakota briefly, I'd also say that the Dakota touchscreen is a bit less functional than the Oregon one, purely because it crams the same interface onto a smaller screen. Maybe it's just my podgy fingers ...
Basically there are 3 choices to make -
1. neat cyclecomputer-style, with USB-rechargable battery - or - blocky GPS-style, with AAs
(all the above use AAs)
2. big screen (in a big box) - or - small screen (in a smaller box)
3. touchscreen - or - button-driven
Big or small screen is a very personal choice. Me, I think the Oregon is too big, on the handlebars.
Touchscreen or buttons - apart from the screen contrast thing, it's worthy of note that the UI is very much optimised for touchscreen use, and is the same on all three models. This makes the Etrex feel a bit clumsy when you're navigating round the menus (it's alright in normal use though). OTOH, there is a school of thought that the touchscreen is a slight safety problem - you really can't use it without staring at the screen, when maybe you should be watching the road ahead.
In terms of facilities, accuracy etc - they're all much the same.