Simon, I have put it through its paces thank you very much, I use it almost daily, and not just on easy to clean commercial seating.
The whole tool leaves much to be desired from a design perspective - it has been designed by an imbecile and certainly wasn't tested for truckmount use before its launch. The vac hose collapsing is just one of its design faults, and one of the few that's actually addressable.
If you could take the vacuum slot off the sapphire and add it to the drimaster 2 you'd have the perfect upholstery tool. So until then....