Roof Ridge Vents question

My framer informed me that there is something called a Ridge Vent with a
ridge cap that is incorporated 6" or so from the peak of the gable roof
and runs the entire length so that you do not need a series of 507 square
vents. Has anyone had any experience with this? Any pros or cons?
I'd appreciate any help.

The cutout for the ridge vent needs to be the right size. A reciprocating saw or Milwaukee Sawzall is great tool for cutting the roof to the correct size. If the fitting is too small, it
cuts down air flow or you have no air flow. Too big, poor fitting, loosely
connected, may leak. The ridge vent needs to run the full length of the roof, not stop at where
the soffit starts that I've seen on some. This leaves the soffit poorly ventilated. Don't step on aridge vent, its made of mild plastic and will break. The roofing nails for the shingles that go on top of it need to be longer than those used on the sheathing. See its directions. The appearance is hardly noticablely changed at the ridge when finished. The ridge vent is the outlet/exhaust for hot air. In order for it to work effectively, a counterpart inlet/intake of fresh air is required. A few standard soffit vents isn't going to cut it. See the soffit at jameshardie.com When properly done with a counterpart appropriate soffit venting, very effective. The application directions are in the box. Some makers have 'em online.