this is my opinion
if +7 Garm CM is like 18m, +8 is like 22m, +9 is like 30m and +10 is like 40-45m
people would pay more than 20m just for that +3 extra def
and let say u have +8 armor +8 muffler, +8 shoes, +8 guard, +4 kaho + pcb
to me it is worth it than +9 armor +9 muffler, +9 shoes, +9 guard, +5 kaho
and +9 gear is harder to get compare to pcb
of course PCB only worth it if u aiming for high def for pvm