I notice that the conversation reverts again to grand regulation. the original question was about a vertical piano.
I am probably typical of piano technicians in that my sense of "good regulation" is much more certain in grand pianos than in vertical pianos.
This is the case even though I have tuned more vertical pianos than grand pianos.
Grand pianos are the "high end" of our work. I've rebuilt many grand piano actions, very few verticals.
Taken as a whole, many of the verticals we service are not well designed, many are intentionally B- grade instruments, not capable of fine performance regulation.
In the last years of my career I did a lot of field service for a Yamaha dealer who was very concerned that his pianos were well-prepped and followed up in the homes.
After servicing a few dozen quality vertical pianos over their first seasons, I began to develop a critical feel for vertical pianos, but not with the point-by-point clarity of grand pianos. This is probably innate in the action.
I had one opportunity to play a late Fandrich vertical piano. It felt very much like a grand piano, but even more responsive. I've wanted on ever since.