They are saltwater nerites, so if you get them and just drop them into freshwater, the shock will be too much. I'm not a nerite expert, but I do know that most nerites can swing both ways, but they must be appropriately acclimated.
However, as you mentioned, most SW nerites look significantly different than FW. With that, I'd say pass.
Virgin Nerites can be acclimated to freshwater, and people did so years ago, before the recent surge in availability of freshwater/brackish Nerites. If I'm not mistaken, they can be found in freshwater rivers in some part of the Caribbean, though ones on sale are likely collected from saltwater areas along the Eastern coast of the US.
But then again, I've completely forgotten what those snails look like, so if there's more than one snail being sold as "Virgin Nerites", this could be useless.