I have an Asus EeePC myself too, the 1005PE, but im using Lucid 10.04 instead. Ive bought it soon after Lucid was released, and decided to stick with an LTS release. After all, netbooks have limited hardware, and i depend on it on a daily basis, for work and college, so bleeding edge is not needed, stability and long term support comes first.
At least in my particular combination, the Fn+F2 key works perfectly. I can (and i do) switch wireless on and off several times a day. Sometimes I have problems turning bluetooth on and off, requiring restart, but since Eee900 has no bluetooth, it shouldnt worry you.
Also, I didnt have to install any driver. The ones out-of-the-box recognized my harware, from touchpad to wifi and even bluetooth.
So, my suggestions are:
Why not try Lucid 10.04? Its LTS, so it will be supported for 3 years instead of 18 months.
If you dont use Maverick's Unity, youre already missing the biggest change in that release. So Lucid will look very similat to what youre used to.
Power consumption in Lucid is smaller than Maverick. For a Netbook, battery life is crucial.
Ive downloaded and installed Jupiter. Not for the Fn keys, but for power management. I strongly recommend it. It really improved my battery life from 8 to 12 hours. HUGE improvement. Check out my answer on a similar question for some info about Jupiter. And yes, it also improved Fn control by enabling OSD Notifications for every Fn key, and it does have independent bluetooth and wireless enable, something my Fn keys do not.
So, why not try it? Lucid 10.04 + Jupiter may be your solution for the Fn+F2. Even if they dont, you wont lose much compared to your current setup (Maverick minus Unity is almost the same as Lucid), and you will get some side-benefits as well, battery life and LTS support to name a few.
You dont need to touch your HDD to try it... use a Live Session to see if Fn+F2 keys work. You can even install Jupiter in a Live Session. Or repartition your HDD to have them both installed side-by side until you feel safe about it.