I have the same scope mentioned on my 7mm rem mag, so pleased I bought a second 3x9x40 Conquest for my MLer both saw plenty of low light action and couldn't be more satisfied. I compared it to my Leupold Vari X III and a new VX III it is both brighter, sharper and clearer. POI tracking has been right on the money and it hasn't moved zero (this after being straped in a koplin gunboot for 2 - 1 week hunts in the forest). The z-plex reticle is another feature that sold me on the conquest, it is a very good day and lowlight hunting reticle to my eyes it seems to jump out when I acquire.

The only nikon I viewed this year was a Gold with limited real comparison (in store and behind) the Gold and Conquest stood pretty much equal and better than VX III IMHO. Now that I have a true fixed eye relief scope I really like it and both the Gold and Conquest offer this.

Never tested the Monarch so can't comment.

Good luck, hope it helps.