Garmin 200 is excellent for the price.
I took a wrong turn cause I misread the map, and even though I went off the route by a few miles, it still showed the route (at varying scales),
so just by pointing myself in the right direction, I got back on the route smoothly.
Taking a wrong turn happens rarely, and you can tell a few seconds your going the wrong way.
I like to set a route 30 miles ish at the moment, somewhere where I haven't been, and then I will just follow it.
Its fun to see how far you've gone, and the speeds, (on strava) after completing journey.
Battery life seems very good too, but you can pick a £1 battery on
ebay to charge it on longer rides.