Of the smaller tools, the Squirt sets the standard. I tried the other minimalist ones, they are aggressive in carry and just too small. The Squirt has decent tools and rides without chafing. So, it stayed. Next best was the little Gerber Bear Grylls, which are lighter duty but heavier to carry.
The Utilikey is useless except for the tiny screwdriver. I carry it when we have newbs on staff and the rumor of our "Basement" storage room comes up - I have the key! In others words, I get more out of it as a joke than a tool.
I've seen some rely on the keychain screwdrivers, they take up space, and the weight of a massive keychain is the #1 reason ignition key cylinders on cars fail. With the newer fobs, nobody carries much on a keyring now, unless trying to impress others with their access to numerous locks which obviously need masterkeying.
So, with minimalism in mind, nothing on the keychain more than the house key and the car key are needed. I use the Leatherman Sidekick now, no pouch or holster which minimizes the BatBelt look. It has enough decent tools on it to get by, I'm using it today to install a stereo in my old Subaru Forester. The flat phillips does ok, the short file/screwdriver is a reasonable pry bar, just don't overdo it. Multitools are just that, compromise designs, and they simply cannot be the best needlenose, or best knife, or best screwdriver. The Sidekick is passable, the Wave or Vic Supertool clearly outclasses it, but they are twice the price, weight, and require a pouch, too. It's all a matter of tradeoffs.
There are a number of choices because each user decides how much tool they need to have on hand - and how to carry it. Much beyond that and something else gets involved, especially among male users, and it's the old game of who's got the biggest tool. Hmmm. Aside from that, there are tools that were given very little thought toward usefulness, and those that go one step too far. Those who own a Superchamp Victorinox and never carry it know what that means.