Ok, this is actually a very cool invention. I was thinking I'd get it for the car dashboard or just generally have it in my pocket or messenger bag.
I'll start by saying this is not putty-like the ones kids use. This is actually quite hard and has a much more rigid texture.
That's actually the pro: makes it a nice playable surface with tons of rebound. Think Vic Firth Heavyhitter pad.
But it's also the con: it's hard to take out of the box, hard to mold flat, and it's noisy :P
Still, love it. I will be making good use of this.
Still haven't decided if I'll carry the vic firth practice tips, or this, or both