My Skeletool is my first "proper" multitool, bought as a replacement for a semi-novelty keyring/keychain tool I'd been given as a gift.
I find that a major factor in the usefulness of a tool is having it to hand all the time which, for me, means attaching it to my keys. If it wasn't part of something essential I'd find myself leaving it behind, which would invariably prove to be at the time I really need it. So when I started looking for a replacement tool I initially considered the Leatherman Juice, which is suitably compact, but to get one with all the tools I wanted (corkscrew, file) I'd be looking at the top-of-the-range Juice Xe6, which is a bit strong on price and full of things I wouldn't use.
So I decided to sacrifice the extra tools and started looking for something more minimalist, which is when I stumbled upon the Skeletool. It's compact and light enough not to be a burden, the carabiner makes it easy to connect to (and, importantly, quickly disconnect from) my keys, it's got the tools that I use most often, and it's about half the price of the Juice Xe6 which must make it the best value tool on the market!
Apart from the cool and distrinctive looks of the Skeletool, the thing that I've found most beneficial is the excellent quality of the tool. The blade is exceptionally sharp and hasn't dulled at all in my six months of use, and the finish is as tight as the day I got it. The bottle opener is also very good and, when you've got the knack, the carabiner gate grabs the bottle cap once you've opened it, which is a cool (albeit probably unintended) feature.
There is, however, one obvious downside; there aren't many tools. That's not to say there aren't enough to get by, but you do need to be skilled in the uses and abuses of tools to get a good level of versatility, and it would probably come up short if you want the correct tool for the correct job all of the time. But if you're happy to improvise; I've found the blade and pliers sufficient for most tasks, and the selection of screw driver bits is reasonable, although they could benefit from a bigger size difference between them.
I've given the Skeletool four stars not because of any disappointment in ownership, as it's actually been better than I expected, but rather because you have to make sacrifices to have one, which means it's not perfect. It's still very good though...