I have Z1 for 2 years (200 jumps) + 4 hrs in tunnel.
No problems with it except narrow angle of side view.
Now, it’s not that important to you. But in couple of hundred jumps, if you will do more serious RW, it may. Try to look behind while in arch. Z1 have the narrowest angle of most full-face helmets.
Now I have Factory Diver, it has the best side view, lightest, simplest, cheapest.
The reason I didn’t get the Oxygen, was inferior flip visor. It’s not as solid as Z1’s, doesn’t flip all way up, and may open in free fall. Besides, having Z1, I found that I don’t use flip visor as much anyway.
Also take a look what best teams use, that’ll give you an idea.