I used to use the ultra synthetic filter but I got a deal on K&N PS-1010 so I bought a bunch of them. Since putting the first one on, I've noticed lots of engine noise on startup. I called K&N and they are having me send them the old filter for analysis. I have a Purolator One (PL14610) sitting on my desk as a replacement for whenever I get around to it. I'll make an update after I hear back from K&N. The ultra synthetic filter seemed to do a good job, but for $9 I have started to look elsewhere (Purolator)
__________________________________________
View my fuel log 2015 Mirage DE 1.2 manual: 42.7 mpg (US) ... 18.1 km/L ... 5.5 L/100 km ... 51.2 mpg (Imp)