Brian,

I just wanted to add that the RAM mounting ball fittings are very easy to work with also. They're cast aluminum & easily drillable or can be cut easily for fitting in odd-shaped areas. They come pre-drilled with lots of holes, but they're more like a 3/16" hole vs 1/4" that I feel allows a more common wrench (7/16") size.

If you look at the gpscity offerings you'll see some popular combinations. I think those were better buys than individual items....but look for yourself. They're all interchangable, as long as the balls are the same size as sockets.