Yeah, that's actually one of the coolest things about open-e. The modular nature makes it cake to swap stuff in and out, and the fact that linux (what open-e is based off of) has all the drivers built-in makes it all super easy. The new flash modules that Open-E uses has write-leveling built-in and a Write Endurance of at least 2,000,000 times. (I checked.) That's as good as you're going to get. Remember, a mirror doesn't protect you against a software error. So, it's actually better to have that second flashed module ready, sitting on the shelf (even if it isn't activated, yet).