Both TMR and MD are designed to be rangefinding reticles primarily. The accuracy of interpolating (for rangefinding as well as zeroing) between stadia is about .1 of 1 mil (.1 mil) for the std. MD. For rangefinding with the TMR u get .1 of .2 mil at .02 mil accuracy (80 % better accuracy). The TMR also allows for .1 of .5 mil or .05 mil accuracy for downrange zeroing. The std. MD only allows for .1 of 1 mil once again (.1 mil) or 50 % more accurate.
As far as i've seen the TMR is the finest, most accurate reticle system ever designed for the milliradian.
How is it better than a NSX Mill line reticle, a S&B P--4 Fine reticule or any other made along thes same lines?
The NSX Mill Dot reticule is circles that you can see through and I find it to be excellent as well.
Just looked at the P-4 S&B reticle and it also has .2 mil line stadia so it would have the same rangefinding accuracy. But the NXS MLR reticle will not be as accurate since the finest stadia to stadia gap is .5 mil. This provides for .05 mil interpolative accuracy (.1 of a subtension unit is about as accurate as i've seen anyone guess with any level of repeatability), whereas the TMR has .2 mil allowing for .02 mil accuracy (again .1 subtension unit).