My first choice is to use the ridge vent first to attain the minimum recommended vent area of 1.5% of attic floor area. Add pan vents as needed to reach the desired exhaust area for your roof. Ridge vents are naturally at the highest part of the roof and exhaust the best. Pan vents are the next best thing because they are mounted a little below the highest peak of the roof.
Both forms of high roof exhaust are improved when soffit intake vents are installed to provide a cooler, lower air intake to wash the roof sheathing and replace the hotter attic air.
Powered roof vents have about a 10 year life and are best used only if really needed due to the natural convective air current caused by hot air rising to escape out the ridge vent or pan vents in the higher parts of the attic.
My company, Mosby Building Arts can help design effective attic ventilation for your home. Call our office at 314.909.1800 or contact us here.