I was hoping someone else would have written a review before I chose it as part of my pick 5. I'm still pretty new to magic so I'm not too familiar with the concept of glims. I ordered this item out of curiosity and I have to say that I am completely neutral with this purchase. The gimmick is cleverly hidden and does as it's suppose to do. However, I don't see myself using this any time soon. I much prefer card forces or card controls over the grumble glim. To be fair though, the grumble glim does have practical uses outside of card magic. I may end up using it more in the future (when I can find good routines that pair up with it nicely) but for now it'll probably sit in my drawer.
I wouldn't pay full price for this item but it's not a bad deal when you get it in the choose 5.