Why is it so good?
Well, I can see the burrs on the heads of the screws holding the target numbers to the post at 55 yards away. That's not bad for a start, if you want something to fine focus on.
If you can't tell when it's sharp and when it's not sharp, then the scope is no good for accurate rangefinding, that's how I see it.
Optically it knocks the pants off the older big Nikkos and they are widely used.
If your scope wheel is a bit stiff to turn, do what I did. I took the small wheel off (just one small screw holds it on) and found a piece of wooden dowel just smaller than the inside of the wheel. Wrapped some 600 grit wet and dry round the dowel and with the aid of a power drill lightly worked on the wheel to open it up just a shade.
Using a digital mike I worked out that the standard clearance was enough to compress the two very thin O rings rather more than was necessary, and an increase in the bore size amounting 0.1mm would still retain an interference fit over the O rings but not squash them so much. Checking all the time for progress, then a polish and a re-lube and reassemble.
Focus drift with temperature, has been almost non existent right up until this last cold snap, where I have seen the T35 try to tell me that some targets that I know are only inches short of 55 yards are actually at 51 yards. That was after shooting in minus 6 for about an hour.
The Leup that I had almost needed a slide rule to work out where the index point had to be placed.