I've wanted to pick it up for a while but had just been slacking off with ordering it, then my roomate got it for me for Christmas! I've been riding my SS most of this winter and so far only have two rides with it on my Rush.
The first ride was at Lewis Morris, I didn't have to use it but it was nice not to have to put a multitool in my jersey pocket. I noticed it vibrating a bit on some of the downhills.
Then Saturday I rode with it up at ringwood. I will start off by saying that the instruction book says to take the plastic cap off of the top of headset and place it on the bottom before using the tool. However I've lost three of these caps and my LBS charges something like $15 for a piece of plastic that is worth $0.15. So I didn't have one to put on. Regardless I had 2 cases during the ride when the tire lever and chain tool separated from the multitool and fell through the headset onto the ground (presumably the plastic cap would have caught them had it been installed on the bottom of the headset). After the 2nd time I gave up and put them in my pocket. Then I got the opportunity to use it when my chain broke. I found the chain tool extremly large and clumsy but usable although slow.
So in the end while this product is amazing in concept and the type of product I love to see Cannondale come out with, in practice I have not been happy with it and do not recomend one.
I'll try to rig it better and give a follow up review in a few months.