I work at a hospital and a contractor finished up a building of ours with about 65 Diakin indoor units and four big roof top units. My concern is that every airhandler they installed above the drop ceilings has big holes cut out in the return plenums. Dont know much about the Diakin's or how there installed. And the filter setup sucks also, you just about cut your fingers trying to get the filters out, and you need a hanger to try to hook the filter thats behind the first one. Just seems slopp to me. Any one familiar with these?