Greg,
It's a different method that achieves the same thing. The FabBoss has several advantages:
1. You can bolt the device to a FabBoss (or a set of them) then tack weld directly into place. No precision drilling required.
2. A welded FabBoss will never fail in service. Be honest, you think about the nut insert spinning every time you tighten the fastener, am I right?
3. The FabBoss can be quickly trimmed to fit irregular surfaces. Good luck doing that with a nut insert.
4. You can weld FabBosses to tubes. Drilling holes in tubes for nut inserts always leaves chips inside the tube to rattle around, and usually requires a tack weld so it doesn't spin.
5. You can get your MIG torch into lots of tight spots that you can't get your drill into. Let alone the nut insert tool.
6. With a FabBoss, the bolt and insert doesn't protrude into the space on the other side of the sheet metal.
Nut inserts have their place, no doubt. But FabBosses have lots of advantages. I think quality car builders ought to have a supply of both on hand.
And to be fair, I owe you guys some photos and videos about how and why a FabBoss is useful. Bear with us... it's coming.