If it were me, I'd take a look into March Scopes offerings - First
ZCO and Tangent are head to head - i think it would be good to youtube some reviews though as I believe Tangent takes the lead there for some aspect I forget why, but its gnats hairs.
A lot of the differences in top teir scopes are also more ergo's and user preference features
such as Kahles reverse direction CCW turrets
Don't forget IOR
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I own a Kahles and really like it, I bought it for being robust, a field scope, no brass, no plastic
Steel internals and tungsten balls for the detents, for ELR I am a turret twister.
---so the Kahles is great other than one thing
After 400-600 yds - the Focus - (parallax adjustment on the side) really does nothing further
I like to be able to adjust Focus at 2000 yds
The Kahles did not allow this, basically it is in focus and parallax free from about 400 yds on out
Some experts say - this is an attribute of a high quality optic
If that is true, then I guess I should not complain.
But I am used to my being able to perfectly dial in focus at 1 Mile such as with my B&L scopes
not that the image is at all fuzzy with the Kahles, it's just that even at 1000 yds, the parallax could be dialed in on the 600 yd mark, and you would not notice any difference from if you turned it to infinity.
Someone pointed out that if you are jumping back and forth between yardages, you can set parallax at 400 yds and jump back and forth between that and 1000 and not have to readjust the parallax
This is true, and I do like it for that aspect, I really do not have to adjust parallax back and forth.
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But with the Parallax - Hard to explain but, say at 2000 yds, I like to be able to adjust focus PAST where it is sharp at the distance, and adjust further toward infinity to where the image is fuzzy again
then dial back to sharp again,
So for this feature, I would not choose the Kahles
I even sent my Kahles back to Austria factory asking them to allow/ put in, more parallax adjustment
They must have laughed not understanding that some of us...........shoot wayyyyyy past 1000 yds
and sent it back to me untouched - not even cleaned
They must have done their in house function test and called it good according to their standards
But the Kahles glass is amazing for my eyes - it will literally see right through mirage
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You might ask Eric Cortina how he likes the Kahles 5-40