I still think the inside mounting is the best. There must be some reason that FWC went with inside mounting for the factory installed setups. Maybe you should call Stan or Chicalli at FWC and talk to them....ask them what they recommend. They have a lot of years of expertise...why not leverage it?
The guys are great and all but gas springs have only been added to the campers in the last year or so. I wouldn't just blindly assume they have heavily researched and tested this issue at this stage. Maybe they did prototype out multiple types or maybe they just spent a little time to find a something that worked okay.
Long story short I wouldn't just dismiss the exterior springs that some other customer has on their rig, esp. without hearing how well they work or not, just because FWC isn't doing it factory currently, both manufacturers have in the past incorporated improvements that were first done by customers.
Personally I hope the exterior springs show promise because the idea of having to deal with removing interior springs when popping the top (they'd be in the way of getting into bed in my setup) is not appealing at all. As it stands right now I can handle the camper fine without springs but the wife can't so I'd like to improve that situation.
To add your confusion, mounting the gas shocks on the inside the way FWC mounts them will aid in raising the rear of the roof if the front is raised first. Doesn’t help as much if you raise the front section first. I don’t think mounting them on the outside front will do anything to help with the rear section as they are too far forward to add to the leverage. FWC installed the 60 pound struts on my Eagle recently and they really work slick!
Put a set on each end.