I have used both Amsoil 20W-50 syn Motorcycle oil and Amsoil oil filters with great results. I have experienced some very small oil leaking at the filter. It should be noted that Amsoil changed their oil filters from a Synthetic Blend medium to a Nano fiber (full synthetic blend) filter medium. The Nano fiber material was developed for the military for use in the Abramas Tank and Apache helicopter. I haven't used the new filter yet.

The new Nano fiber synthetic filter is rated at 98.7% efficient at 15 microns, synthetic blend filters are rated at 80.3% effiecient at 15 microns and paper filters are rated at 30.3% efficient at 15 microns.

With the new filter and oil Amsoil warranties it for twice the manufacturers recommended changed interval or 1 year, which ever occurs first.

Those who would give up essential liberty to purchase a little temporary safety deserve neither liberty nor safety. Benjamin Franklin, US author, diplomat, inventor, physicist, politician, & printer (1706 - 1790)