MERV 11 does the trick during pollen season in Florida changing it every 3 weeks during Jan-March. Will try backing off to every 6 weeks when the worst is past. That appears to be the recommendation for highly allergic individuals, on a routine basis, throughout the year.
I'm very pleased. The filter fit perfectly and was shipped promptly. I read other reviews and I will say my experience was great. I will definitely order again They were a better price than my local supply store.
So, its difficult to be excited about air filters. But I would say that the experience with this company is always a good one. They are always professional and the product arrives quickly. So there you have it. Exciting stuff, huh ??