Wow, I guess I messed up the question some how.
Can I use a MERV 16 filter in my system or will the pressure drop be too much for the system? Will I burn out the motor?
If someone had a four inch filter system and wanted to get the best alergen filter, what do you recommend?
Do I need to supply more information? Or are there too many choices and not enough known about various filters on the market to really recommend something?