The Mobil 1 oil filter is made by Champion Labs who also make the K&N, old AC-Delco’s, STP, Wal-Mart supertech and more, all these filters are well made and generally follow the same layout and manufacturing technique, all are better than Farm. The more expensive brands also get thicker base plates more and different media and other changes. The M1 is packed with a very thick paper element, lots of surface area,
Don’t know if I will run the M1 when I run out of 20004’s, there are questions about its restrictiveness and it is expensive. I may then look for a free flowing cheap coarse filter to catch the big stuff (Wal-Mart) and worry about fine filtration with an oil guard bypass filter.
A note about Champion filters, on the base plate there is a stamping letter code, all filters with the same base plate threads, seal diameter etc will have the same stamping, this makes finding alternative filters easier.
Read more
http://www.oilfilterstudy.com/
http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=forum;f=6
And search here, many, many, threads on this subject