Garmin 810

[Oxo]

I've seen the dcrainmaker site and it doesn't help with my specific question.

 

[Erudin]

I find the accuracy and detail of the free OpenStreet maps excellent.

I downloaded the Routable Bicycle (Openfietsmap Lite) UK map from http://garmin.openstreetmap.nl/ as a single image 523MB file (gmapsupp.img), then copied it onto a 2GB microSD card. The 810 loads the maps automatically when switched on.