Outstanding revolver! It will handle all the .357 loads you'll care to shoot out of it. Great larger L frame is a stronger design, but larger and heavier and therefore not quite as good a snubby CCW design.
Your 66 is a K frame. I have a 3" M-13 K frame that is at least 30 years old. Was well-used when I got it almost 15 years ago and I've shot the snot out of it with everything from light .38's to heavy .357's. She's as tight, accurate and reliable as the day she left the plant.