I think 3940p makes a lot of sense from the collecting perspective. The overwhelmingly positive feedback is yet another proof that it's well-loved by our collecting community. On a personal level though, it gets a little trickier. I'm blessed to have a first gen datograph, also in platinum. At my current collecting phase, I have a strong preference to give all my watches regular wrist time. The 3940 being an automatic perpetual calendar, it'd be worn on most workdays if I were to acquire it, which means significantly less time for the dato which I still love.
It's a fine line between finding a piece I admire, and a piece I MUST have (now desperately looking for ways to have them co-exist...)
Ken