Rule of
Highly respected brand name watches...200M = 200 Meters Vertically, under water.
No name watches/most replicas...200M = 200 Meters From The Boat Dock Horizontally, above water.
All kidding aside, I have not (knock on wood) had a rlx type acryic or sapphire case leak after resealing (or replacing) the case tube/crown, crystal, and gaskets. One exception is case corrosion...it might not leak today but it never gets better.
All cases were tested at 90psi to 100psi without the movement after lubricating the gaskets/case back threads with Krytox etc. Always perform the first test w/o the movement because with 'Dunkin' Donut' type water testers...any small leak can sometimes blow the crystal off and flood the case.
Also with 'DD' type testers...properly working He valves will usually let air bubbles OUT at first if there is a leak, sometimes followed by water if the case is not pulled out of the water quickly. Defective He valves may let water IN. He valves can be a problem if not maintained, checked for corrosion and gasket defects.