Hi, I have a Volant intake with a Volant cone filter. The filter got a little squished so I wanted to replace it with a new one. Do I have to replace it with another Volant? I was at AutoZone the other day and they had K&N ones, as well as an "off brand" on hand that claims to pull the same amount of air for half the price! All these filters look identical, they r the same size and all are able to be cleaned and re-oiled. Is there really any difference between the $60-$80 Volant or K&N, and the $30 one? Thanks!