Nikon has a quick focus eyepiece, so you can quickly find the optimum relief at any magnification.
The Nikon Monarch EER is very clear also, as good as Leupold.
My Bushnell Trophy tends to have more distortion near the edges and very sensitive to eye position relative to the ocular.
Bushnell also has a fixed eye relief, 2X- 6X have the same relief.
The Nikon eye relief will vary with magnification but you can correct it with the fast focus eyepiece. This optical design seems to be more relaxed to head position.
FWIW, I have 3 Nikons and 1 Bushnell Trophy...The Nikons are on my .223, .357 Mag, and .44 Mag, Bushnell on the 17 HMR.