I went with the Topeak Pocket Rocket. It’s a simple 1-piece unit that was light and cheap. Some pumps use a hose, which I’ve see as a common failure point so I wanted to avoid that. I’ve only had to use it a couple of times though, so I can’t say a lot about dependability. It has good reviews though.
I’ll second the Topeak. I’ve had the same one for I don’t know how long (at least 10 years) and may have used it close to 100 times. Always gets the job done.
I just got a Lezyne since there is no place to put a “real” frame pump on my BMC Road Machine. My plan is to never use it ever, but better safe than sorry. Anyway, I got it mostly because of good reviews from people I know and from an article in Velo. I got the larger of the two so it’s not really pocket sized if that’s your interest. I think the smaller model would be though.
The main thing from the reviews that attracted me was the quality of the pump and the number of strokes to 70 PSI. If I do have to use the thing some day I want something that will actually put air into my tire…
I use a Topeak Road Morph G, might night be the lightest or smallest but it’s a great strong (140psi at least, comes with a guage) pump, that fits on a frame.
I have a sks super short. It works, and it fits in a water bottle, which is where I keep my flat kit. I used to have a topeak road morph. I liked it but the rubber wore out and it doesn’t fit in a water bottle so I got the sks.