I have Gilles Berthoud fenders on two of my bikes and a pair of vintage stainless steel Weinmanns on another.
- 42mm tyre + 50mm fender + vertical dropout = perfectly fine > Gazelle Lausanne. Designed for 37mm tyre.
- 35mm tyre + 45mm fender + Shimano dropout = deflate tyre to take the wheel out > Batavus Randonneur GL. Designed for 32mm tyre
- 37mm tyre + 50mm fender + reversed horizontal dropout = deflate tyre to take the wheel out > Koga-Miyata SilverAce Designed for 32mm tyre
My preference from this is 37mm tyre with 50mm fenders that are about 10-15mm above the tyre.