The Switch looks like to sell 100m units unless Nintendo cuts its lifespan short like they did with the GBA. Nintendo will be able to push the system to its limits for a while, and we'll still get many PS360 ports and the ocasional 3rd party exclusive, so 100m is achievable, especially if they make more affordable versions of the consoles. 150m, though? Too much. No other videogame console is ever going to reach PS2-DS levels, too much competition from all sides nowadays, not to mention the rate of evolving technology is cutting the consoles' lifespam shorter and shorter.