I personally have the Remington 870 combo which I got for a steal 10 years ago when I worked at a sporting goods store. I love the gun and it is still a pretty good price for it today. I also have the Mossberg 500 which for the price cannot be beat. You can get teh combo for extremly cheap right now and for a few months at D icks sporting goods. It comes with everything you need for deer hunting as well as anything you will need for upland game hunting. You may want to replace the scope because it is quite cheap, but it is still fine to harvest a deer with. Personally, Id go with the combo over a single shot unless the single shot is far less expensive. With the combo, you will have a gun for any type of hunting you want to get into or if you already have another shot gun, its always great to havea backup. With the Mossberg it is literally ready to go out of the box after you have sighted it in.

I have an Rem. 870, 1100 - both good guns. I bought my son an H & R 20 ga. slug gun this year and between him and I we harvested 3 does and 1 buck. The gun is a reasonable price and shoots great.