folders and location of JVC file

I think I have sufficiently confused myself enough that I need help.
For some reason my two 3597s are acting different. When I connect one to my PC I get a item in File Explorer labeled "Nuvi 3597" with a nuvi_drive blue triangle icon next to it, not a folder icon. There are 2 drive icons under that labeled "Internal storage" and "Memory card".
The other 3597 gives me an actual drive entry labeled "Garmin nuvi (G:)" with a nuvi_drive blue triangle and another drive entry labeled "3597-5453 (H:)" with a std drive icon next to it.

The folders under them are also slightly different.
My POI files are on the memory card under the Garmin folder in a POI folder. The JVC file, which I had to separately download, is in the JVC folder under Garmin folder on the memory card also.

There is a .jvc folder, which is empty, in the internal storage on the G: drive but not in the "Internal storage" folder on the entry that has no drive letter.

One unit also shows a yellow computer and the other a gray computer.

Any explanation for why these are different and if I should rearrange anything. Both units appear to work properly but now I am not sure.