Larger negative vs. weight/size.
I like size and don't mind weight, so I would go for the larger negative size.
Hold both cameras and check how it feels. And if money is a factor, check what extra lenses, film backs, etc. will cost.
Andmaybe more important: what lenses are available and what system has the best lenses?
Ask yourself what you're going use it for. Indoor - outdoor, project - vacation, ... Then ask yourself if it would be easier to have a smaller camera or larger negatives.
And what size of negatives can you print yourself in your darkroom (or scan) at home?
Bert from Holland