First, I would recommend you look at a used Leupold or a Burris (get for around 200 or less), lifetime warrenty and fast turn around if it is sent in for warranty work. 4x is pretty rough to shoot offhand with a pistol. I don't know how you hunt blacktail, but a ski pole/shooting sticks or something might be a benefit to have with you. I go back and forth between 2X and 4X scopes and neither is perfect for me. I think a good 1-4x would be optimum on a contender. I have run 2X, 3X, 4X, and 5X scopes on different barrels on mine. I put a 4x on my .22 pistol not long ago and practice with. It definitely helps.
Nikon makes a decent scope, but I have heard of customer service problems with warranty work (3rd hand could be a rumor).