g'day Mirror,
I am not cabin crew for Netjets but there's about 3 "Netjets" operations in the world. There's USA, Europe and Middle East. I am not familiar with the US or ME operation but am reasonably familiar with the European operation.
You're contracted to work 18 days a month. Generally they'll try and give you 6 on 4 or 5 off to fit the month. The flight attendants work on the large cabin fleets. Namely the Falcon 900 & 2000's as well as the G4 and G5 (550's) too. The G5+ are the ultra long haul aircraft. (ie London - Tokyo sort of thing). The rest do medium-long haul with short trips too.
From what I can gather the atmosphere is what you make of it. You'll either have a great time or a lousy time. It just depends.. It isn't typical airline flying and the service is much more individual.
Have a look on their website for more of an idea as to the fleet, the cabin layout and the type of operation Netjets has.