When it comes to air filtration, pleated filters are the clear choice over fiberglass filters. Pleated filters are more efficient, safer for the air and HVAC unit, and are not significantly more expensive. They can filter out the smallest particles, which is important for people with sensitivity in the air. They are less likely to clog in a short time and can last up to 90 days.
Pleated filters are more durable and last longer than fiberglass filters. These should be replaced every 90 days, unless you have a large family or special conditions that create excess pollutants in your home, in which case you may need to change them a little more often. For reference, a pleated filter of only a MERV 8 rating filters at least 75% of particles between 3 and 10 microns. The two most important factors when choosing an air filter are cost and air quality: homeowners want their filters to effectively control air quality without having to pay a fortune for it.
Pleated air filters are now constructed of synthetic materials that have smaller individual fibers, which are wound in such a way as to maximize airflow and filtration efficiency. The woven fabric then filters large and small particles of contaminants from the air as it is drawn through the oven or HVAC system inlet. While the airflow advantages once enjoyed by the fiberglass filter have been innovated basically without style, there is another element of system health that is not often discussed, and fiberglass is surpassed by pleated filters once again here. Oil companies with good technicians warn that they should use fiberglass filters in HVAC systems and use separate HEPA machines for whole-house air quality.
So the answer to the question is technically yes, fiberglass filters allow better airflow, but the difference is largely irrelevant to the HVAC system and its health and efficiency. A shorter HVAC system life that results from using such a useless filter will end up costing you much more in the long run than the additional six dollars every three months to buy a pleated filter. Puron's replacement of Freon, along with some general improvements in HVAC construction, have lowered demands on the HVAC system and made the decrease in airflow from using the pleated filter enough to keep the system running smoothly. When it comes down to it, pleated air filters are what you should be looking for for your home.
They are much more efficient, safer for the air and HVAC unit, and are not significantly more expensive than fiberglass filters. CHANGE PLEATED FILTERS EVERY 3 MONTHS OR SOONER IF YOU SMOKE OR HAVE PETS OR IF YOU HAVE AN UNUSUALLY DIRTY ENVIRONMENT.