I'm contemplating buying a Progression ST II from a guy I know. He wants 350 bucks for it. It's probably 8 years old but it's been in storage for 5 years. Would that be a fair price? He doesn't have any tools or a calibrator with it. If anyone has experience with this particular model, I'd like to hear about it. I tried stringing a test racket on it and had some issues with kinking my poly strings at the clamps and at the linear gripper end of the crank. Any thoughts? FYI that was only the second racket I've strung so it could be user error. I learned on a Neos 6000 that was significantly more advanced.