Sienna X or Nouvatan

I am completely new to Salon Geek, but my head is bursting with looking at different spray tans, so would really appreciate your help!!!
Have looked into the Sienna X training but since reading through lots of threads on here, Nouvatan keeps popping up with great reviews.
The threads are quite old so was hoping for an up to date review on theses spray tans.
Any help would be greatly appreciated...