I have the squirt s4 and p4 (very cheap on ebay), as well as the wave.

But for it's size and weight, I think the Juice s2 is the best tool. Scissors are excellent - better then any leatherman except the 3/4 pound surge - pliers work for anything but the biggest jobs, and good selection of other tools. It weighs 4 ounces, and a little big for a keychain.