I have a N90s (roughly equivalent to F100 size/bulk) and OM bodies. I prefer the OM due to it's smaller size; though these older eyes prefer the AF.

But if you plan to carry an SLR with only the 50mm lens on an everyday basis, keep the F100 and buy an older RF with a 1.7-1.9 lens (Canon, Olympus, Minolta). You lose nothing and you gain a 2nd camera with complementary capabilities.