These picks are mainly for exercise and practice, certainly not for live playing, etc.
Pros:
-They are quite durable if you are using them properly. (see cons)
-They are easy to get used to and help greatly with technique.
Cons:
-If your hand is heavy, their durability is questionable, even though I personally never broken one I can imagine how one would.
-They are a bit slippery
In short, they are great for picking practice, and not so great for any other purpose.