I am one of the owners of THG Heat, I can certainly provide some insight : )

The THG has a slightly thicker laminate, which I think provides a better look and feel in hand. Performance wise, THG heat tape is reported by users to produce more consistent heating across the surface and length of runs.

Most significantly is the rivet connection system that we use for the THG heat tape. We use a rivet and eyelet connection, as opposed to the old style alligator clips. The rivet provides a very solid and strong wiring connection to the heat tape, the wire is actually slipped BETWEEN the lamination and secured in place with a compressed rivet. Properly installed, it is much more secure, and more resistant to loosening, or disconnecting, than the alligator clips, which have always been a bear to work with.

You can see a gallery of heat tape pics, including rivet details, here.

You can use the alligator clips with THG heat tape, if that is your preference, but you cannot use the rivet connectors with flexwatt, as the buss bars are not wide enough. You can make a solder connection with either brand, if that is your preference, and we include both rivet and solder instructions on our site, linked above.

Let me know if you have any questions!

Robyn@THGHeat.com