Well I've been using the product for some months and the only reason I haven't gone back to a traditional key ring is that I haven't gotten around to it.  I'm sorry to say that I don't like the product, because I was hoping to.  It is much more difficult to add keys than a traditional key ring.  Once they are in there, because they are stacked so neatly, they store well.  However using them is a problem.  You typically have to use two hands to choose your selected key.  Because they are all stacked up, it is not easy to identify the key you are looking for.  With a traditional key ring, you can easily see all the keys holding them in one hand, and you can easily select the intended key and unlock a door.  The Key(not so)Smart, is cumbersome to hold while unlocking a door and difficult to go from one key to another in cases where you have to go through two locks.  Unless I'm just missing something, this is not an improvement over a traditional key ring, other than the keys store more compactly.  I would call a traditional key ring a far superior and economical choice.