I use my Squirt P4 (the older one) all the time. The file, the pliers (think of them like ridiculously overbuilt but still supremely accurate tweezers and you'll quickly discover how useful they can be), the awl and the drivers; at least one of these tools gets called into duty every single day. The blade is soft (420 or similar steel) but it takes a pretty good edge and would definitely serve well as a teensy backup blade. I retired my Micra because of the file and pliers on the Squirt and I don't regret it for a second. The PS4 includes a small pair of scissors that work okay (not as well as those on the Micra) and that also puts it ahead, in my book.
I bought a Chive for my wife and she uses it regularly, but what I didn't like about it was the miniature frame lock, which is not very compatible with my medium-large hands. I can close it one-handed, but I don't like the extra caution and effort involved in doing so, safely.
If the choice were mine and I already had a nice full size knife, I would buy the Squirt instead of the Chive a thousand times over and twice on Sunday. The added utility of it will serve you much better in the long run than an additional standalone knife. But if you like your Micra enough not to feel the need for a Squirt, then by all means, go for the Chive... but I'd still choose a different small, backup blade.
