What will happen to my snippets in TextExpander version 5, 4, or the Mac App Store version if I try TextExpander for Mac version 6?

The first time you launch TextExpander for Mac version 6 it will import your snippets from any older version of TextExpander and add them to your TextExpander account.

TextExpander for Mac version 6 stores its local data in a different file location than your older TextExpander version, so if you revert to an older version of TextExpander all your snippets will still be there.