There are a lot of options out there. My wife and I currently have two trucks (an '06 1/2 ton and a '96 1 ton) with B&W's. I really like their system and they are a very easy install in most trucks. We did both trucks ourselves and the 96 was way easier than the 06, but both were done in about 2 hours. My only qualm with the system is that it is easy to leave the ball unlatched if you do not have your head on tight when you are hooking up (many arguments and long days have started out with me reminding the wife to always lock the ball in place).
The 96 had a reese king pin/rv style system in it when we bought the truck and that looked like a good hitch, but it was definitely in the way. Reese makes an adapter that pins in just like the Fifth wheel plate so you can pull a gooseneck using the same mounting rails. We sold the hitch to buy the B&W because we liked the idea of everything being out of the way when want to use the truck bed.
Before the B&W became popular we had several trucks with a piece of channel iron laid across the frame rails under the bed, plate welded to the frame and a nut welded on the bottom side so you could remove your ball similar to the B&W. Worked well enough, but I believe most people are shying away from this style of hitch because of the liability involved in welding a modern truck frame and because if you are ever in an accident the insurance companies are going to look at every possible item on your truck as possible contributing factors to the accident. This system is considerably less expensive than the B&W, but I wouldn't recommend going this route.
As a side note, when you cut the hole in your bed measure several times and check the directions from B&W carefully. Also, if you use a hole saw to cut the bed find a scrap piece of plywood or MDF and bore the hole in their first, then you can put your knees on it and it will help to keep your saw from wandering as you cut the hole in the truck.