If I may share this here, today I greased seals and WP tested my recently acquired XF V5 blue Pelagos, and it passed without a scratch.
Alternate tests 2 times at 6ATM/ 2 times at 3ATM, with 3mn pressure building each, for only 2 or 3 bubbles escaping from under the insert (remaining air).
I'm sure it could take more pressure, that rep seems to have a real diver potential, solid !