The little battery that came with the Shogun is not going to last long in a dive. I am using the Sony NP F970 with the Shogun on land. The monitor is pretty power hungry. More so if using spinning disc and raid. Good thing is that the Shogun has many options for batteries including cine batteries with D-tap.
Tested mine with Samsung 850 pro SSD with 1 TB. Works No need to limit to Scandisk Pro SSDs. Samsung is so confident that this SSD will run and run they offered 10 years warranty!
What sort of recording time are you getting with the NP-F970 battery? I flattened the standard battery just by playing around with the settings options, although I tried most of the options.. In Aus the SanDisk Pro also comes with a 10 year warranty, before which time it will be either be lost, flooded or superseded.