Hi, Eugene.
Best to just experiment with a few rolls.
I would start by shooting a 25-50 ISO film in good weather, and going from there. If you live somewhere where the sun doesn't shine clearly that often, maybe start with a 100 film instead.
In the sun, a 400 film can get printable shots, though they will be quite thick.
The lens seems slightly wider than normal to me. Perhaps 90-100mm equivalent or so, which is slightly wide for the format, although I really have no clue what the FL actually is.
BTW, if you want to thin the herd, let me know.