I prefer a pod that has the least amount of clearence off the ground that is required. I like the 'Tango Down Advanced Combat Bipod' it is very well made, easily removable when you don't need a pod, and can store up towards the shooter. Great product but expensive.
I use a GG&G bipod. It's real job is on my Blaser, but since it supports the rail interface, it does find its way onto the XCR from time to time.
Is it worth $180? I think so. You can save a few bucks by going with a Harris bipod of some sort, but I think the GG&G unit is easier to adjust and a bit more secure. I also prefer the feet on the GG&G.
I had one of the higher-end Harris (swivel, reverse locking notched legs) units but ended up selling it when a friend of mine decided he had to have it for some project. I just looked them up. They're still just under $100, but I'd also still rather have the GG&G.
I agree with Sloan441. I really like the GG&G. Even though it looks big, it's actually a fair bit lighter than my Harris on it's YHM mount. The Harris works well on my AR becuase the gun has more weight towards the rear. On my XCR, which has more weight up front because of the gas piston, I like the lighter GG&G. It's a little more money than a Harris, but once you factor in a mount, it's not a lot more expensive.