I think all the engineers that read this can agree that Hydrogen has many uses. But Hydrogen seems to be rather inefficient. I would propose the engines be more efficient to make them more practical. While the engines are nice, and the abundance of hydrogen makes it a good option for vehicles, there is a downside that you need a o2/h2 Generator to go far with the vehicle. And I prefer to keep the vehicle as cost effective as possible. In survival, I will on occasion find my self driving pretty far in a ground vehicle since they are far easier to build. The farther you go from where you land it is probable that you will come across rough terrain, such as the infamous rippling effect that happens on some hills and many of the mountains, making it hard to cross if not impossible. This is fairly dangerous, and the cost of losing a vehicle with 1-2 Hydrogen engines, an o2/h2 generator, cargo, and various other mechanical parts, could prove to be too much. But I would like the ground vehicles I make be more independent from the refueling areas that I set up. This way I can get more done, in less time with less RTB for refuel. I am okay with the power output by these engines, as many of my vehicles will stay with a 4x2 or 6x4 frame for work, and the one HE is more than capable of running a simple cargo truck without any real trouble. I think that Hydrogen Engines should be more efficient, or that there be a module to make the Engines more efficient and a module to make the engine more powerful to take on more strain should it be needed. I appreciate your hard work, and I hope it only gets better from here.
Images attached to this topic are some examples of Hydrogen Engine vehicles. Some of these vehicles shown have o2/h2 generators, how ever some do not. This is either due to lack of space in the vehicle or the design chassis predates the use of Hydrogen Engines.