If you never ride out of cell coverage, no worries, you're all set. I'm out of cell coverage 5 minutes east out of my front door, and many of the roads I enjoy have no coverage. California, the land of wide open spaces, wonderful motorcycling roads, and crappy cell coverage.
Here's a map of TMobile's coverage (our carrier) near me. Alot of that white space sure has some great roads in it...
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Annie and I did a motorcycling tour of Europe a few years back, and one of the things that amazed us both is that no matter where we were, even on top of a mountain out in the middle of nowhere, we'd still get great cell service. Pretty much the entire trip! May be like that in other parts of the world, but it's not like that here in the US in general, or in California specifically, unfortunately.
(I just loaded the pic into your post. There's no need to resize on this board, just load it as an attachment and the board will automatically resize it if needed).