I recently asked ULF shooters, and particularly in 717 format, which focal length lenses you preferred and for what types of subject matter.

Sandy King commented that his favorites (in 717 format) were 240 and 300 Computars, 450 Nikkor M, and 600 Fujinon-C.

Question for everyone: what do you like about the effect of getting longer and longer beyond the logical advantage of merely having increased reach? Do you particularly like the inherent optical tendencies such as less (wide angle) distortion, compression of space?

What, specifically, does "wider" get at - optically for you (that so many seem to prefer and say is a "natural" for aspect ratios like 717/820/410)? What does "longer" get at optically for you?