I have had a couple of angel investors tell me tales of similar products...I thought they had little chance and when I heard Bloom had gotten 400 million in this story I realized that it takes deep deep pockets even to try the idea.
There is a company called violet fuel cells that has an interesting patent that would allow high enough power densities to allow SOFCs to enter the transportation market. They went silent about two years ago, I'm hoping they got funded and are going to introduce a product soon.