What are you trying to achieve?
sds5150; What is the motivation for providing filtration? Is it to protect your HVAC unit's hardware or are you seeking to improve the "health" quality of air circulating within the conditioned space?
As far as "work well?" what parameters constitute Well? Are you in need of removing particulate down to a certain diameter? If so what diameter?
General consensus for a "cleanable" filter type is they are good for maybe two or three washings, then have to be discarded owing to adverse restrictive effect on the system (a.k.a. pressure lose across the filter, typically measured in inches of water column).
My sincere advice is to check directly with the vendor of your unit as to what they recommend/require.
Personally I put a 4" Media filter in my Child's system since he doesn't seem be able to remember to change it out in a timely manor. It goes up to 12 months before it needs replacement. If you have serious health concerns please consider an EAC (Electric Air Cleaner) they do work. One of my clients is an EPA scientist who monitors the air quality in his conditioned space. The EAC was effective for about three weeks after which it starts to fall off (decline) rapidly in effectiveness. Only required a trip through the dishwasher to bring the EAC's filtering element back up to near 100% effectiveness.
As for "good" that's a value judgment which needs qualified, understood? However here is an on-line provider that I have used. They did conduct business in a professional manor.
Hope this helps...
[Edited by faith on 06-13-2005 at 08:02 AM]