Although my cheap Costco Garmin works pretty good with Open Street map sometimes I need to look actually to a map to see my position, which is not exactly available on the Garmin. In these occasions I use the Pocket Earth Pro app on  my phone which works excellent even without data package. Just download all the maps for off-line use. For an extra zing I downloaded the GPX files from iOverlander website and uploaded to the GPS. The same files I sent through email to myself, opened the file on the same phone where I have the Pocket Earth App and opened the GPX file with the app. The only trick is to turn off the Single Track option. I chose the colour and shape of pin and voila they are all shoving up on the offline map. If there is a number, zoom in, there are multiple pins close by.