Tom,
Same here, never hurts to have a spare. Helps to keep Murphy at bay. I was so unimpressed with the white Kubota replacement filters that I never used them and switched to WIX. I really wish I could still get the original factory units. They were much better construction. I opened them up and maybe they are overkill. Could be Kubota decided they didn't need that much filtering. I think the manual even says to change the filter every other oil change (or is it the other way around, have to look it up I guess /forums/images/graemlins/confused.gif ).
Later days,
Michael