Globe, if you are planning to swap the spiders yourself, you'll need the little Cannondale tool and a vise. (It can be done without a vise, but it is not easy, or advised.)
Chemist - I had Zero Gravity brakes for awhile. (Some of the Planet X stuff is of a similar design.) I didn't notice that they stopped any better or worse than anything else. But, they were an absolute PIA to set up. They never wanted to stay straight. I finally just gave up and sold them. Went with Sram Red instead. They work fine with a variety of pads.