Comparing to the 3M filters I'd been using: Thinner by close to 1/2 inch and fewer pleats ... which means less surface area for filtration. Otherwise they seem ok. Quality of construction looks ok... although in1 filter (out of 6 I bought) a corner of the pleated material wasnt attached to the frame... (allows some unfiltered air past) Way cheaper, but I'm thinking that I might go back to the 3M filters for surface area and QC.
Both replacement filters were the same as the ones being replaced. Even though tight fit, no problems getting them into the cabinets. Price is right, so satisfied overall with the filters and purchasing process.
These filters work very well at filtering out allergens and make it much easier to breath. They are less expensive than the April Aire filters. I highly recommend them.