I went for the 1000, but have now sold it and gone back to the 810. It has a fab screen, but the main two things for me were battery life and capacitive screen.
I did a lot of controlled experiments on battery life. If you have it permanently on a data screen the battery life is not too bad – around 10 to 12 hours. If you leave it constantly on the OS map screen this reduced down to 5-6 hours. I like to use the map screen a lot, especially when riding abroad so this was a bit of an issue. Similar controlled trials on the 810 showed very little difference between ‘constant map’ and ‘constant data’ displayed, with both configurations consistently achieving in excess of any option on the 1000.
The other issue was the selection of a capacitive screen by garmin. It doesn’t like some gloves, and in the rain it can become extremely erratic – sometimes locking the device (i.e. stops responding to screen input until you unlock it) and other times difficult to get it to do what you wanted it to.
🙁