I have no objections about using saltwater jerkbaits in fresh water. As a matter of fact I have seen good catches of large mouth bass with the Smith Saruna and some other SW jerkbaits. The issue comes up, in my humble opinion, when using top water lures, especially poppers. I purchased a SW Yo Zury popper and cast it into a lake: It did float but it would stand totally vertical, that is, by no means leaning which is the position I am used to seeing. The popping action was made by retrieving too fast or at least faster than with the regular FW poppers. Difference in buoyancy might be an issue because salt water is denser (about 1.03 g/cm3).
I would like to know if someone have successfully used some SW topwater lure in fresh water fishing.