I just had a new system installed. The contract included a Merv 16 whole house air filter. He installed an Ultravation progressive Media Merv 11 filter box and filter. He said he couldn't find a Merv 16 locally and told me to buy a filter and he'd deduct it from the total invoice. After doing some reading it appears that Ultravation doesn't make a Merv 16 and it doesn't seem like the filter box is universal; at least from what I've read on the internet. We have family members with allergies but nobody smokes in the house or anything like that. So my question is: Should I make him replace the whole filter box with something that can take a Merv 16 filter or should I just leave the Merv 11 Ultravation? In other words, beyond principle that it should have been a merv 16, does the Ultravation have any "pros" that make it worth keeping over a 16 cabinet and filter?