I'm using ztsd 3 on /home and ztsd 1 on /. Cant run compsize on / because it fails hard if it finds a permission error
compsize ~/
Type Perc Disk Usage Uncompressed Referenced
TOTAL 88% 293G 330G 345G
none 100% 268G 268G 273G
zstd 30% 16G 53G 63G
prealloc 100% 8.5G 8.5G 8.6G
compsize /usr
Type Perc Disk Usage Uncompressed Referenced
TOTAL 71% 56G 79G 79G
none 100% 47G 47G 47G
zstd 28% 8.9G 31G 32G
compsize /var/lib/flatpak
Type Perc Disk Usage Uncompressed Referenced
TOTAL 55% 8.6G 15G 30G
none 100% 5.0G 5.0G 8.9G
zstd 34% 3.6G 10G 21G
User data is mostly compressed to begin with on my end so the difference isnt what you'd call huge but i'll take it over literally nothing. Its "free" as far as my usual usage goes.