I use joints plus joint radius to build pentagon tubes for the hand mesh. It's fast, looks decent, is easy to work with, and is consistent across platforms.
It looks like the Oculus runtime is reporting joint radius as half size or something. My fingers are the correct size on other platforms, but Quest gives me dracula needles instead 🙂
This is on a Quest 2, using the 1.0.13 OpenXR SDK published on 2021-02-19.