Sound like you've got it set now. Something I've noticed over the years is that certain bows do like certain string materials. I've had bows that felt really harsh with low stretch string materials that became sweet as sugar with B-50. I've also experienced the opposite where a bow had a bit of handshock or vibrationwith B-50 but calmed right down with a low stretch material such as 450+, 8125 or D-75. Sometimes you've just got to play around with some different things to get the most out of a bow. Most of my bows sport 8125 strings except for two. One is an older bow and the other just doesn't like the material. You can feel a vibration through the riser when using it, so it sports a D-75 string.