Definitely. This makes me wonder how other Android implementations store it though, as the space for brute forcing a 4 (or even 8) digit number is so small as t

Definitely. This makes me wonder how other Android implementations store it though, as the space for brute forcing a 4 (or even 8) digit number is so small as to be essentially nonexistent, as long as you're cracking some kind of hash rather than typing in attempts.