Every saw I've owned have let a few fines into the intake. Never been a problem though...
Yup...
Basically any used saw I've purchased that doesn't have an immaculate filter has some fines in the throat.
I actually owned a 372 xpg that had been run with the winter filter all its life from what I could gather...even that saw was fine and plenty strong...
I actually knew a jonsered dealer in NH who, when I was ordering a flocked filter for the 372, told me that I wanted the 80 micron winter filter (but didn't address it as such, just by the part number), and when I asked why I was told "that's the better filter"
I agree that nobody wants their saw eating dust, and especially if youre in the desert and there's lots of sand in the wood or whatever it's more of a concern, but a tiny bit of seepage here and there does not seem to be that big of an issue to me. A lot of saws are run with fairly dirty air filters..just ask some dealers on here...