In reply to mattrm:
I have in the past used the grigri, grigri 2, cinch and the click-up, I now own only one of these which is the grigri 2.
The click-up has a problem that unless you stay ahead of the climber in regard to slack, if they pull up on the rope it locks and is the hardest of all of the devices to release.
The grigri and the grigri 2 both work the same except that the 2 works with thinner rope. Paying out rope quickly you place your first finger under the curved metal edge and place your thumb on the cam, his is also what you do if it locks up mid clip.
The cinch looks really easy to pay out rope if you have it right, I spent an hour with someone that uses it all the time. They can almost throw the rope up to the climber it is that smooth, I however still cant feed the rope
As for the weight being a concern here are the weights without a carabiner, Cinch 182g, Click-Up 115g, GriGri 170g, the weight difference is about the same as an extra meter of rope (Edelrid Boa 9.8mm TS Duotec 62g/m, Petzl Contact 9.8mm 60g/m, Tendon Smart 10mm 65g/m, and the lightest that confirms to single rope Beal Joker Unicore 9.1mm 53g/m)