Well mrgl02, whoever you are, if you really want to know how good the Honda Filter is compared to other get the SAE test results from the ones you want to compare to. All filters have to undergo SAE (Society of Automotive Engineers) tests to prove that they meet the engine manufacturer's requirements.
Good luck getting them from Honda as they consider all techinical test reports to be Propiatary Information and will only release it as a result of actions by orgs like the NHTSA. When you get what you are looking for why not post it for all to see.
The SAE J806 test uses a single-pass test, checking for contaminant holding capacity,size of contaminant particles trapped, and ability to maintain clean oil. As an amendment of the J806 test, the multi-pass test also looks for filter life in hours, contaminant capacity in grams, and efficiency based on weight. The efficiency of the filter is determined only by weight through gravimetric measurement of the filtered test liquid.
Typical numbers for paper filter elements are 85% (single pass) and 80% (multi-pass). A new test, the SAE J1858, provides both particle counting and gravimetric measurement to measure filter capacity and efficiency. Actual counts of contaminant particles by size are obtained every 10 minutes, both upstream (before the filter) and downstream (after the filter), for evaluation.
From this data filtration ratio and efficiency for each contaminant particle size can be determined as well as dust capacity and pressure loss as a function of time. Typical numbers for paper element filters are 40% at 10 microns, 60% at 20 microns, 93% at 30 microns, and 97% at 40 microns.
A good filter has a strong steel can to withstand the high oil pressure from 60 to 80 PSI when cold, an anti-drainback valve that actually works without creating too much backpressure, a pressure relief valve that doesn't leak, and a strong paper element and cap that can with stand the pressure and flow of oil without falling apart.
The element media has to be able to trap small particles without restricting the flow too much. Cellulose (paper) media is used on economy filters and works OK (read FRAM or Honda or any of the low end filters like EMGO). The fibers in the paper acts as a mesh to block particles down to a certain average size, while allowing the oil to pass through.
Some manufacturers add other media, such as cotton, to the cellulose to improve its performance. There is synthetic fiber media for the high-end filters that has smaller passages to trap smaller particles, but can pass more fluid through it because it has more of them and there is also media that is a blend of these two.
There are also "Depth" filters that are usually made of synthetic material that has a passage size gradient to it. The deeper into the element the oil goes, the smaller the passages get. This way, large particles are trapped in a different spot than small particles, which allows the filter to hold more particles before it becomes too restrictive or "blocks".
Now please tell us how the Honda Filter measures up when compared to any other filter of your choice. I don't know the answer to that because Honda just won't tell what the SAE results are for their Paper Element Filters that come from a variety of different sources over time. You have to consider that Honda, like so many others, buys from the lowest bidder then markets it with their own part number.
Jerry