I had one of the first edition Bushnell 700 yd series. It would give accuracy +/- 3 yards to about 500- 700 yards then out to 1,000 yards +/- 10 yards worked well, just had to have a definitive background. Meaning we shot in a field that was 1,000 yards deep and 500,600 wide and glassing with the thing would give us relatively good results on some of the little hills,,especially if it had a woodchuck on it standing up. but the flats where the grass looks like an infinity pool, not so good. That was over 10-15 plus years ago. We walked a lot of the yardage and it was on. Gave it to a friend... the one's ones now are faster calculating.
hope it helped.
Tex