I don't know the answers to that - but I always find the ocean blue wetsuits interesting.... I did see half the dive team was diving with inspiration rebreathers and HMS Explorer dive computers.
And about a minute before the end of the show last night, there was a quick shot of someone in a Drager Dolphin (lower-cost SCCR Nitrox rebreather, for the uninitiated, only good for 130' max).