There is no last-mile problem. In cities with excellent subway systems everybody is a very short walk away from a station. In Paris, for example, no building in

There is no last-mile problem. In cities with excellent subway systems everybody is a very short walk away from a station. In Paris, for example, no building in the metro area is more than 500m (6 minute walk) from a metro station. If PRTs like this can be deployed more cheaply and widely than subways (one of their main goals), that means you can bring that down even more - perhaps 200-250m. There are very few people that cannot be served by system being a 3 minute walk away from them.