I have been reading a lot of the hho threads and i can answer almost all of your questions, i dont have the time to hunt them down and then compete with the people that think the earth is flat.
Not everyone is suited for driving small cars in a smart way. I am nearly 7 foot tall and i have a size 15 foot. the only way i get a geo to move is if i throw it.
hydrogen is a viable solution and i do actually have a working model, i dont have the numbers you want right now, but that is only because i am to busy stress testing everything. i build my own cosm and my own pwm. if you want to learn or ask questions feel free. If you want to nit-pick and annoy i dont have the time.