The Canon 1Dx2 has this type viewfinder level also but I really don’t use it much. It also has a level as part of the Info button functions that works on the rear LCD. More for leveling on a tripod in my opinion...
KTJohnson wrote:
My camera, fairly old now, a Sony A77 has a level display, both for horizontal level and front/back tilt level. I don't know how many others have this.
Using those can make the composition level TECHNICALLY, however, sometimes I have to tweek it in Lightroom to make it LOOK level.