RE: 1 pin site vs. multiple pin site
Some decent responses by the guys. Both types of sights have their merits. Each has it's draw backs, too.
Personally I like a single-pin-adjustable for hunting here in Pa. The single pin obstructs your field of view less. You can't pick the wrong pin. If you have a bow that shoots about 260fps or more then you can set it for about 25 yards and shoot anything from 5 to 30 yards, without doing any adjusting. For the occassional longer shot when you have time to range the animal and everything is right for the shot you have the ability to move it. You can use the same sight for practice and 3D where longer shots may be the norm.
Multi-pin sights have been around for decades and proved themselves so there isn't much to say about them.
As BigJ said, it's really a matter of practicing with what you choose and becoming intimately familiar with it
I'm kind of anal about things like this so make suggestions based on my personal experience. I do not like, and will not have a sight with any plastic on it. Plastic is some thing that can be made cheap and it's what you get---cheap. It can break (I've done it), rattle, or just plain be a pain in the a$$. A good sight should have a metalpin guard that encompasses the pin (s) very well just in case some twig should try getting at the fiber optics. Bright fiber optics without an artificial light source is paramount, too. I don't need to have a battery go dead at the wrong time, and usually when you can't see your pins it's time to get home anyway. OH,, it's gotta have metal pins also. Plastic just doesn't get it.
In a single pin adjustable Windsor has a good idea with the HHA OL-series. I use an OL-5000, IMO, one of the best hunting sights of it's type.
There are lots of sights out there. Maybe a thousand of them by the time you read all this. Look at them all and take your time. By the time you get done looking you can bet someone will come out with something "new and exciting".