I haven't had them long enough to evaluate. They just got here 4 days ago. Besides how am I to know how good they are or aren't. I'm trusting your web page.
Filters ordered were supposed to be 20x24x1. They are actually 1/8 to 3/16 less all around. Easy to put in, but are they large enough to actually correctly seal the airflow, do they allow too much leakage around the edges? Personally, I don't like to have to force them in, but I only have to do that once a month, so how much bother is that? I am not really satisfied, and would recommend AGAINST anyone buying them because they think that they are buying a premium filter. They do not seal well.
After researching your filters, I bought six of your best. They are costly but would be worth the price if they worked. We have had the filters in two weeks now and as I am typing this my eyes are itchy and we are still sneezing. I will not order any more filters because they don't change the allergens flying around.