I have the S/E stage 1 A/C and have been pleased with.
The screamin eagle air filter kit includes a k&n style reusable filter. If my memory serves, K&N even makes the filter for the kit.You can always get the HD SE Air Filter kit as part of your Stage 1 upgrade and then stick the K&N filter element inside as your budget permits.
Yes, you have to clean and re-oil the SE filter.And you don't have to oil the S/E filter!