As I experienced it myself and many other from what I see in the forums, the Field Shelter serves very little purpose. Other than a constant but meager 0.5 power generation, a simple buggy or tractor offers the same benefits of transmiting power and generating free oxygen plus a save point, with the downside of not being mobile like a vehicle. Carrying a packed T2x2 platform, the player has a more versatile option for the same space of a T1 slot, power generation is almost always also brought in by the player in the vehicle used for exploring.
The only real benefit of it could be when use