From the fellow BOTLs that I have talked to, most of them have said stick with distilled water. Some of the cons with using solution is that it will wear out the medium you put it on. So if you have a sponge it will make it stiff and unusable after a while.

I had a friend who had me take care of his humidor and he used the solution. I'm not sure how long he took care of it for but it looked like the humidity pack he used had a bunch of crystallization on it.

I'll stick with beads and distilled water.