[Synchro909]

I've used them, sort of. They are 0.2" over size but I didn't like the idea of removing good solid, original cast iron from right where the Model A block is already prone to cracking. I didn't want to put hardened seats in so my compromise was to reduce the valves to 0.1" oversize. That still meant a new seat higher in the block but not much cast iron gone. Even with that, it is my best breathing Model A engine.
If I were to build another engine, I think I'd put the larger valves in with seats.