""That sounds Expensive and exotic. If PMF works, and fiberglass is stronger, then there seems to be little reason to go chasing exotic materials for some small gain in strength. Could you make the while teardrop, including frame out of Gr/Ep (graphite/epoxy)? Yes, but it would be mind-blowingly expensive for not that much gain. Just my opinion.
I have checked 6 oz fiberglass cloth costs off internet against Basalt. For a 4x4x8 box, no floor treatment, the cost of the fg cloth is $134. The basalt cost would be $369. I don't know what the relative strength factors are. I have read that S glass is stronger than E glass, but much more expensive. The same source says basalt is stronger then S glass, and cheaper. Basalt cloth is also much more puncture resistant. So if one layer of basalt is sufficient, rather than 2 or 3, then maybe it is worth it.
I am wondering if selective use of Basalt to reinforce joints makes sense. Or maybe, as you opined, if PMF is sufficient, and FG better, just use FG as a reinforcement and PMF for most of the non-joint areas. If I go the DIY route, I'm spending $1500-$2000 rather than $17500 for a ready made. What's a few hundred more for super strength and no penetration issues ?