Camera and satelitte info
Pocket Wizard will work with the Fuji X series.
The X-Pro-1 and X-E2 have low light abilities equal to your D300s.
The glass is rated very high competing with Leica.
I own one and only use my Nikon in the studio.
A lot of info on DP Review and other places.
Instead of Spot check out the Delorme InReach SE They have a one year plan and after that the subscription can be monthly.