I've had a petzl rig for 3 years and it is a good tool, made for heavier climbing line, 11mm works flawless, 10mm it will slip some if there is no
tension, under a little tension it doesn't slip, locks up and works fine once it catches with the 10mm, I don't think it is advised for that size
with 11mm it is very easy to tend and repel with and you can lock it up when set at desired height.