Terry. My Bighorns were built in the 80s. Curved bed. They came with dacron strings, of course, an I shot them that way for years. Don't know exactly when I switched to D-97, maybe 15-years ago. I didn't do it for speed gain. I did it, and continue to use D-97 on older Bear TD limbs, for example, because it reduces limb vibration at the end of the shot, making for a more pleasant shooting bow. Makes the bow feel less spongy and more solid at release. The extra fps is just a side benefit.
I do pad the loops to fill out the string nocks, which greatly reduces the possibility that the material will saw into the glass there. Too, D-97 is not as thin or as hard a fiber as some other low stretch strings. It's primarily the very thin diameter, hard material low stretch strings that occasionally cause problems, particularly skinny, low strand strings without padded loops.