I have a Mark 6 with the illuminated TMR. Its an amazing scope. The eye box is more limited on 18x, which is to be expected. Really, I don't shoot much above 12x. But, if you're at the bench or really want to get into it you have that 18x option on a scope that is the same size as a 2.5-10x. I think thats where it shines. In a form factor of less than 12" and 22ish ounches you have a 3-18 scope. Locking diopter is nice as well. Set it and forget it. Parallax adjustment works well too.
I also have the short MC52 turrets. I find they are much better than even the turrets on my NF 2.5-10. The clicks are more tactile and audible. Tracks perfectly. The illumination is better in the Mark 6 than the NF as well. There are no dead spots, its perfectly even and well thought out. I didn't like the push button illumination on my 1-6 Firedot or the NF 2.5-10. Pushbuttons just don't work that well on scopes unless they are separate buttons, IMO.