I have a FUji G617 with a 105 lens and like it a lot. The width of the final image seems appropriate. WHen I view 617 images made with shorter lenses I feel like there is too much space crammed into the width. Also, as the lens get shorter, there is a need to get closer to the subject so that the subject is not too small on the film. I would say go with the longer lens as a starter.

I also have a homemade 4x10" on which I put a 165mm Angulon.

The third in the pan arsenal is an X-Pan with 45 and 90 mm lenses. Believe it or not, I use the 90 more than the 45. Perhaps this is becasue with this small film the details are too small witht the 45.

Have fun!