I use an F3 as my primary phone. I bought it in late 2006 just to avoid making an investment because there were a lot of rumors at the time about a new phone made by Apple.
One of the biggest advantages for me was dropping out of the feature-upgrade rat race entirely. My phone is exactly as out of date now as it was when I bought it and I expect to have it at least another 10 years. It looks brand new, sounds great, is easy to use and has an insanely long battery life (though a dictionary would be nice!)
It's not for everyone though, and I can see how 'downgrading' might be difficult (especially for addicts).
One of the biggest advantages for me was dropping out of the feature-upgrade rat race entirely. My phone is exactly as out of date now as it was when I bought it and I expect to have it at least another 10 years. It looks brand new, sounds great, is easy to use and has an insanely long battery life (though a dictionary would be nice!)
It's not for everyone though, and I can see how 'downgrading' might be difficult (especially for addicts).