I've ran that setup for about 5 full bags of dust.

This setup is actually based on some of the designs proposed on Bill Pentz
DC conversion page:
http://billpentz.com/woodworking/cyc...Conversion.cfm

I use the same filter as he suggests (FARR 125154-005). The key to keeping
the filter clean is the piece of window screen that I've installed between
the seperator and filter. This keeps everything but the fine dust out of the
filter.

Fine dust does get in the filter pleats after some heavy use (especially
sanding and routing). It can easily be removed however by giving the filter
a few taps.