The more I play with the B&W conversion, the better it gets. I think you will always have to find the best conversion workflow for your taste, for each camera you have. When using a new sensor this alsways takes some trial and error but then everything comes together and bingo. After that, conversions won't take you long at all to finish. My problem, still, is actually seeing in B&W. This isn't an easy thing to accomplish and really does take a lot of practice, sometimes years.