Ive been ordering these for 6 or 7 years now and they work great. We have to big labs and it stops the dust and pet hair and smells. Use to use the mev-13 but the air didnt move as well, but the 11s work well and the price is good compared to buying at a local store.
My last pleated filters didnt make any noise. This one makes a bit of a whistling noise when the air handlers running. Not enough to be annoying, but I wonder if its indicative of a longer term problem?