When you can live (and shoot) with the fixed magnification of 35x or 40x the Leupold Competition scopes are very good. Low in weight, very good image quality, large gaps on the sidewheel between 40 and 50 meters, available new and not crazily expensive like the March. Downside? No reticles with dots or hashes available as standard. But they can be upgraded to mildot by Leupold Germany for 150 euro plus shipping cost.
(prices on the internet are from 1000 USD, Leupold advertises the recommended sales price. I can recommend http://www.arcadian-sales.com/Mercha...ld_Competition
When you need a variable magnification and considering the small price difference when bought new these days I would choose a Sightron over the Nikko Stirling. Better glass resulting in a better image. The only downside compared to the Nikko is that you need a close focus adapter to focus on the targets under 15 yards or you need to turn down the magnification for those.
If you are willing to or crying to try something new: http://benke-sport.de/epages/0c46145...22SB%20FTII%22
The new Schmidt und Bender Field Target II scope that has according to S&B and German FT shooter Adam Benke solved the temp shift problems. Has big gaps between 40 and 50 meters on the sidewheel. 2300 quid including sidewheel.