Thanks Marco! I appreciate your opinion on the subject as I know you have used them and loved them for quite some time now!Sir, I suppose the 1904 you are talking about is the 42C? If so yes, the head design is the same and blade exposure is the same, too (this is my experience with my razors). At the same time, the 34C is heavier and could behave a little more aggressively if you use some more pressure. For a quality shave with the 34C use the weight of the razor only during passes.