I had Uni pods on my HawkGt. Marginally more difficult to maintain than K&N but I believe that they block more dirt. They take awhile to dry out before re-oiling--at least the pods do. YMMV.
AFAIK, oiled foam blocks more dirt than any other filtration media available.
HiFlo filters are just paper OE replacements.
K&N are oiled gauze and Unis are oiled foam.