Kevin,
Please consider adding either...
1) some kind of validation, perhaps in an Assign method
or
2)defining constants for the allowable values
to ensure that the DataAccessClass property gets populated properly since there are only 3 strings allowed.
It took me a few minutes and a search in the UT to figure out that I could not add a more descriptive term in the string. After I found out what the problem was, I found the note in the help...which I obvioulsy missed.
Along the same lines, I recommend that you update the help by adding comments to the places where you show code populating the DataAccessClass property noting the allowable strings.
Thanks,