I do not know if I read your posts good enough but in your first post you said "a long tour". Walking, biking motorcycle, car or?
This is important because if you have access to power and do not have to carry it in your hand you can go for a heavier, larger unit with limited battery time. Otherwise it should be lightweight and with standard AA batteries with long battery time.
Typical first category is Montana and second category etrex or gpsmap64. Or if you can get your hands on a gpsmap60Csx you have the overall best of the second category.
As long as you are out in the free the reception of all units are good enough so that is not a problem, I ave an old 276C on my motorcycle and I never experienced any problem with reception (except for tunnels but no gps works there ;-)