Context: I'm a Grizzly fan though it may not sound like it here. Until very recently my only disappointment with them was the decision to close the Muncy store.
So here goes. The leveling screws provided with the T20916 bottomed out without allowing the insert to be made flush with the table. I did not wish to risk ruining the rather expensive inserts (yes, I bought two) while deepening the countersunk holes, so I made a trip to the hardware store for longer screws. Not a big deal? Maybe. But I work all week and my shop time is valuable to me. The drive to the hardware store and back took an hour out of my life, an hour that I could have spend making an insert out of MDF with a router, a pattern bit and some carpet tape--like the one I was replacing. And I'd have had money left in my pocket.
I bought this insert for use in my G690. It should have worked out of the box.
Also, the directions suggested that the insert would be too large out of the box and would need to be shaped slightly. This was not my experience, but this was not a problem. There is a set screw that allows you to adjust for a tight fit. The insert snaps in and stays put, unlike the red stock one that needs to be screwed down and even after YEARS leaves red paint on every workpiece. But that's a story for another time ... Bottom line is I recommend the product with the caveats noted.