I have used GenBridge to import UFT projects into TMG several times since September. I have easily deleted those imports from TMG so that I can reimport an UFT project using different import options.
Many people, including me, recommend importing, then exploring and using aTMG 'dataset' several times. So far, I have had to make few corrections after the import. In fact, it is easier to make corrections in TMG than in UFT. As you explore TMG with an import, make note as to what you will want to re-correct using TMG after doing your final import.
There are a few vocabulary changes you will need to get used to, such as dataset for project, and the meaning and use of 'memo' and 'sentences'.
Depending upon where you live, you may find a TMG support group near you. Check out the Wholly Genes website.
Oh yes! When GenBridge imports, it imports a copy of the UFT project. The UFT project (in UFT) is left untouched.