Peabody,
Many of us in this area have added ridge vents and so far I don't know of anybody who has had problems. These vents are located at the most logical point in you attic - at the highest and hottest part of the attic.
As others have said, they are 100% passive and should obviously last forever. And they look much better.
The cost is rather modest and the extra ventilation is well worth it in my opinion.
I'm not an expert, just another homeowner who recently got a "free" roof from a hailstorm and who did a lot of research before making a decision on the new roof.
Good luck, Gideon
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Peabody wrote: Thanks to a convenient hail storm, I'll be getting a new roof. And I'll be switching from cedar shakes to composition. They say that here in Oklahoma, I'll have to provide some additional venting besides the existing openings at each end of the house. The choices appear to be ridge vents or 2 or 3 non-powered turbines. Any experts here with a preference?