well yesterday I noticed a dead pixel in the center of the left screen.
I am quite sure it was not there from day one. But now it is, and therefore the Reverb is going back.
Mura is best described as looking through a dirty window.
But i tried not to focus on it yesterday and have to say just as someone answered above, if you choose to enjoy the experience the Mura is ignored quite fast.
After that I was almost there to decide to keep it and then noticed the dead pixel... game over :(
I also noticed that I should have given the Index more chance. (I send it back 1 day after receiving so did not test much)
Turns out it is quite important to adjust Steam VR IPD in order to get the world scale right.
I did this with the reverb but not with the index (as it has manual IPD i thought its not necessary). And in assetto corsa I noticed yesterday that in the Index the worldscale was way too big. In the reverb it was spot on after adjusting IPD in WMR and Steam VR.
At the moment I do not know what to do... Maybe go triple screen :( But racing with the reverb was the most fun I had with any headset or TV so far.
I am just always unlucky when it comes to tech i want :(