I know how you feel. I dropped my Nikkor 24-70mm zoom, only 18 inches, onto pavement. Cost over $700 at Nikon to repair and fix, and it took a long time too because they had to get some parts from Japan. That kinda weirded me out because I thought since the 24-70mm zoom is thier "professional zoom", parts would not be an issue. However, it is back and all works fine now.
On the flip side of things, I own and use three Zeiss ZF lenses on my D800. All three have taken abuse over the years, and all three are rock solid and razor sharp on my D800. When I damaged my 24-70mm, you could see the loss of sharpness instantly, even on my D700. But the standard, manual focus ZF2's are wonderful.
The other thing too, I tried out that 55mm Otus on my D800, and optically, an amazing lens, but huge and heavy. I do a lot of hiking with my camera gear, so I am not always in "pretty situations". Hell, I once busted up one of my 4x5's by falling in a river years ago. Fixed my camera, but the cut on my head needed a stich or two.
Anyhow, point is, I am a natural klutz, but the D700 and D800 along with the Zf2 lenses have taken everything I have thrown at them (so far
).
so I am thinking, depending on your needs, and where you plan to shoot, what kind of conditions you plan on shooting in, that alone might change one's mind over whether to buy an Otus or ZF2.
good luck either way