I have a 2-car garage with a single 16' x 7' overhead door. It's a
heavy door. The opener is a Genie Pro 98, about 14 years old, with a
screw drive. Very noisy. Sounds like it's on its last leg, and
lately I find that the door occasionally opens by itself.

I need to have my entire opener assembly replaced. A LiftMaster belt
drive was suggested, but I'm not sure what to get. The LiftMaster web
site state that their chain drive is the most popular. I would
appreciate any suggestions as to make and type of opener to get. I'm
very big on quality and security. Thanks in advance.