I did a lot of searching on 238 reliability, a year ago, and found "lots" of people with complaints. My experience with a 238 was extremely positive. SIG heavily subsidized the purchase of a 238 for the prize table at our IDPA match, and rather than just have a drawing for it, we set up a short course of fire, and to get a number for the drawing, you had to shoot. Over 100 different shooters shot the gun over the weekend (500+ rounds), with only one malfunction of which I was aware.
It's not outside the realm of possibility that those experiencing problems with their 238s were themselves contributing to it.
I have yet to even see a 938 locally, but agree that the "penalty" for moving up to a full 9mm seems minor, compared to the 238. Of course, even a small difference in bulk can turn a pocket gun into a belt gun.