Re: £899 - Ouch
IPX5 should also be fine for perspiration and the odd shower. x7 and x8 are really for prolonged submersion.
We used to sell IP65 industrial terminals, they were protected enough for cleaning with high pressure water jets... Although that is way above standard IP65.
We tried IP67, tested it inhouse and everything was fine, took it to TÜV for testing and it let water in. The difference was 2cm in height difference in the tanks - with out mounting bracket to pull the terminal down to 1M depth, we only managed 98cm, which the terminal survived without problems. By the TÜV it reached exactly 1M and those 2cm made all the difference.