These are pretty close in the grand scheme of things. The taxi can pull through the intersection and be in an even more optimal position, but it's rare. The timing is very close when you consider how the taxi often is still waiting back at the light or turns right and parks. As in Concrete Jungle, using the void warp will remove much of the "random factor" at the end of the mission. There's also the possibility of losing the door with the warp.