Yeah, well, like everyone else I began with one, and because when I’m shooting I alternate with Z-mounts, it soon became obvious that having an adapter set for life on each F-mount would make things more fluid. Before, I always found myself with the adapter still on the camera as I was about to clamp a Z-mount on it, or else not knowing where the hell I had stowed the adapter when I needed to use an F-mount... and not enough hands and lens caps to manage all that. Simpler with three adapters, really. No need to engage the brain more often than strictly necessary. I wouldn’t have gone that way with the original FTZs that were quite bulky, but the Model II is much more streamlined.