I got the...
35A100SBOL
$147.00 each
(1) Filter #35A100SBOL
17.5” x 23”
Open-Closed
100 Sq. Ft. of 100% Spun Bond Polyester
99.995% efficient at 1.0 micron and above
Washable
In talking with Wynn, the difference in 1.0 micron and .5 micron ratings was in the independent test lab methodology used. They are both more or less the same filtering capacity... Of course that could be pure hogwash since they didn't put it in print... Either way, Bill Pentz worked with Wynn, and recommends the Spun Bond on his web site. As OCD as he is about dust control, that is good enough for me!
The fact that it can be washed and reused over and over again was for me the tipping point. Save me money, and frustration in the long run.