Yeah they work well in newer engines designed to use them, with high degrees of oil control and fuel trim...
But in older and high mile engines and especially carburetor equipped motors they don't seem to tolerate residue fouling as well as conventional plugs.
All the Bosch plats I've seen have a very thin firing tip wire that is recessed. I suspect that's somehow responsible...
Bosch plat tip
NGK Plat tip
I've put a lot of plugs in a lot of motors...overall going with the OEM type plug gives the best results. I always put NGK/ND in Asian cars, AC/Delco in GM, Motorcraft/Autolite in Ford, Champion in Chrysler, etc...
If you really wanna run plats, I'd suggest going with the NGK version for your application...