@NRR: The problems that I read about weren't so much that the Harris bipods malfunctioned, more that the Harris setup caused the gun to jump when shot, making it not so great for reacquiring a target.
I don't know where you heard or read this, but it isn't due to any shortcomings of the bipod. It's due to incorrect use/bad form.
If you get jump when shooting from a bipod, it's more specifically due to bad recoil management. When I go to matches or am just out shooting with others who are also using bipods, I pretty much see guys using bipods one of two ways.
One way is to man handle the rig. The shooter clamps down on the rifle hard to keep it from jumping. Some guys are big and/or strong enough to make this work.
The second way is to let physics work for you, instead of fighting it. When a rifle jumps on a bipod, it's more because the rifle wants to jump either to the left or right, depending on how you are holding the rifle and the position of your shoulders relative to the rifle. Any vertical jump that you might get is due to the shooter failing to put tension on the legs, which is usually a result of pulling the rifle into your shoulder so that the legs of the bipod are no longer locked up, but are more on the side of being folded up.
The proper way to use a bipod is to first orient your body so that it is directly behind the rifle. You want to have your shoulders square so that an imaginary line across your shoulders would be perpendicular to your line of sight to the target. When you get into position so that you have a good natural point of aim from your position, you then want to load up the legs. This means pushing forward on the rifle with your shoulder, rather than pulling the rifle into your shoulder.
With proper technique, you should be able to keep the target in the view of the scope. I know that the above may seem uncomfortable at first, especially for those that are used to shooting from benches where they side straddle the rifle, but with practice it becomes second nature.
I'm 5'2" tall and weigh between 150 and 160. I'm not a big guy and I don't try to man handle my rifle. I just use a firm grip. Using the above technique, I've been successful with shooting everything from rimfire up to 7 mag.
As for the choice of bipods, the 6-9" models are a good choice. They work well for both a bench and the prone position. I like the swivel models. It really helps when you're shooting from a surface that leans one way or the other.
As mentioned, there are two models of Harris bipods. Yes, I like the Harris. They cost about half as much as other good bipods and take a beating.
The first option is the one where the legs are not notched. They are infinitely adjustable. You just pull them out to the length that you want and tighten the screws. I like using these when shooting from a very hard packed or concrete surface. Being able to tighten down the screws on the legs prevents them from spinning when you load up the legs.
The second option is to get the legs with notches in them. The notches make it much faster to get to the length that you want. The down side is that there are no locking screws to keep the legs from spinning (although you can add them). I like this type for shooting off of grassy and not so firm surfaces where you can plant the legs.
On my Harris, I did add locking screws to the notched legs, so I have the best of both worlds.
