I this year just got a USH with Nikon slughunter scope. I thought about just buying a Bushnell and shotgun scope for about 75 dollars. Then I looked into the Nikon slughunter scope which has a BDC reticule, which has for lines in it, first line is 50, second line is 100, third line is 150, and the fourth line is 200. What you do is put your gun dead on at 50, then when a deer is at 150 yards you don't have to aim 12 inch's high or what ever you need to do. The scope does the compensating for you, so all you do is put the cross-hairs on where you want to hit. Know the scope cost 250 dollars, but if your willing to spend money this is the scope I would get. This scope is specifically design for slug guns.
hope this helps
buckshooter