has anyone used this gear drive?

Thanks everyone I appreciate the feedback. I've always used a quality dual roller and have never had any issues. Gear drives have always been out of reach financially, and I',ve never been a fan of "noisy" drives trying to sound like a blower but, I did like the amount of advance allowed and that it uses a three bolt cam. what I wish I could afford is a dry belt drive with a quick access.
Thanks again,
Bill