K&N Filter Vs. K&N Kit ???

I'm planning on installing a K&N filter on my '98. I live on a dirt road and all of my other vehicles have a K&N air filter. The car is just an daily driver and better mileage would be a good thing.
My question is:
Would a K&N replacement filter for the OEM filter be just as good as the K&N Cold Air Filter Kit (cone filter with replacement tubes)?
Thanks. :)