I am late to the party, but have a bit of useful info for you.
The ClassID property should be an invariant with LabVIEW version. ClassName is another property that gives you the same information, but has been known to change from LabVIEW version to LabVIEW version. Use ClassID if you go this route.
Another option is to use the GetType utilities buried in vi.lib. In LabVIEW 8.2, they can be found in
<vi.lib>\Utility\GetType.llb\... These were created to make it easier to solve the issue you are currently facing. They have not been exported to the palette, so there are no guarantees they will keep their current interface (it is still the same in LabVIEW 8.6) and quality may be below our normal standards, although I have had no problems with them.