Best o' both worlds
I like a rigid fork for going over log piles and slower technical work. But for all day, high speed epics I like my 5" Fox Vanilla w/lockout.
So here's what I did. Since I already had a suspension fork (as you do), I bought a rigid KM fork (which has the same A-to-C dimension as my Fox) and a second headset crown race. Installed the 2nd crown race and cut the steerer to the same length as my existing fork, and wah-la. Now I can switch forks in less than 15 minutes (disc brake takes the longest, and even that ain't long) and ride whichever fork suits the type of riding I'll be doing that day.
It's two, |snap| two, |snap| two bikes in one.
--Sparty