I have a TA01NSN and love it. It sits in a Geissele mount now so even better. The BDC reticle is somewhat accurate (at least on paper) with 69 and 77 gr OTM out of a 16" barrel, which is what I shoot. TA01NSN=14.5" 62gn @2800fps
https://i.imgur.com/TRMMMZth.jpg