I'm not sharp, but I can look things up.

30 micron is about 320 grit product.
http://www.taunton.com/finewoodworking/pages/w00006.asp Otherwise 99.44% of
what you produce is larger, and you still have distance from bag, gravity,
and your body defenses besides.

Not to mention the ability to slap on a mask when doing things which make
fine dust.

Advertising often creates a want where no need exists. If you've got the
money, have at it, and use a bunch of duct tape, because dollars to dogturds
you'll get more from leaks than you get from the bag.

If you've got allergies, definitely get the finest filtration for your
collector _and_ your nose, directly.

"Wade Lippman" wrote in message
...
Bags are typically 30 micron or 5 micron, with a few even smaller.

I understand that a 30 bag will pass fine dust that a 5 bag will catch,
but
it is it really noticable over the other dust in the shop? If so, how do
good brands get away with selling 30 bags?

If you are sharp you will pick up that I am trying to rationalize buying a
30 bag, but need to be talked out of it.