Either one is a good exhaust system. Provided you have enough BUT,
Ventilation system have (2) parts
- Intake (soffit vents) at the lowest part of the roof to let outside air (always cooler than attic temperature) in to push hot air in the attic
- Exhaust Ventilation (to let the hot attic air out in the summer months, or let the moisture out in the winter)
Exhaust Venting can be-
- Ridge vents
- Power fans
- Box vents
*Each requires different number of units to handle the square footage of your attic
A factory certified contractor (not factory certified individual) should be able to explain the difference and be careful some systems will not work on certain houses. This is very important because your shingle warranty will not be valid if the correct combination of intake & exhaust ventilation installed is incorrect.
**Also beware, if you have gable vents they need to be closed off to force air to enter at the lowest point of the roof “soffit”.
***Also beware that the factory says “absolutely” never mix exhaust ventilation or it will void your shingle warranty. Example, never mix power fans and ridge vents.