I have the same filters, but will probably change them within the next month or so.
At the Hatteras Classic Club Rendezvous (Inner Harbor in September), probably the best presentation (IMHO) was by a diesel guru Bruce Mallinson (owns a 61' Hatt, and his company Pittsburgh Power has been successful for 30-40 yrs?). Bruce went into detail on air and oil filters, turbos and answered dozens of questions. He was definitely not a fan of the K&N's (he called them dirt bike filters). He was a proponent of foam covered filters (I don't remember the brand, but I plan to give him a call to find out).
Also - a side note, one of the coolest things Bruce showed us was a powerful set of magnets that fit around the oil filters to attract metal particles to suspend them until the oil / filters are changed.
BTW the HCC Rendezvous was a great event, so cool to see those Hatts in one place and to meet the owners.