So, as I write I'm preparing a long travel by bike and I would like to buy a new portable GPS in the serie Etrex, Montana, Dakota, Oregon, GPSmap 62... sincerly I don't see so much difference between most of those new models...
but I understood that it's actually impossible to use unlocked garmin map on the GPSmap 64...

So, here the important point for me :
- the possibility to use Garmin unlocked map (topo, city navigator...)
- possibility to recharge the battery by USB, I charging by dynamo hub
- good battery autonomy

eventually :
- level curve
- the alert on a waypoint
- Itinerary planning as the sports section (cycling)

Thanks for your help !!!
Have a good day