I've already posted in the general discussion about license requirements but I thought a thread about a four wheel version belongs in this forum. The three wheel version is a non-starter for legal reasons. The stability and safety issues are just engineering problems, I have zero doubt that they can solve them. However three wheels has severe legal implications and those are solvable. Anything less than four wheels is a motorcycle, motorcycles require a special license and they also require helmets. It's crazy that a car with a Kevlar and carbon fiber roof needs helmets but the law says it does and those laws won't be easy to fix. It also won't be eligible for the Federal and probably most state tax credit and rebates. The F150 Lighting which will be lucky to get 2 miles per KWh will be eligible but the Aptera which gets 10 miles per KWh won't, stupid but that's the law. The solution is a fourth wheel. Even if it costs some efficiency I'd be happy with a 500 mile car instead of a 600 mile if I didn't need a motorcycle license and didn't need to wear a helmet.