I have the Petzl, but I'm not exactly crazy about it. Mine is also of the older design, so a new one might be considerably different.
I find it very challenging to get on my somewhat large feet. The clasps are quite reliable, but difficult to operate. I use it with 10mm rope, and find that it isn't too hard to move your foot in just the right way to let go of the rope. Conversely, it is pretty easy to re-attach to the rope with out using your hands, at least with a little height in the tree to add weight to the free hanging rope.
I have never used the Notch, so I cannot compare.