So for $3,500 I get a new laptop plus a 100 inch screen. To buy those separately would be far more than $3,500.
In my case I plan to buy it on day one because I want it for working. I'm tired of having to choose enjoying the nice weather outside while using a tiny 15 inch laptop screen or being inside at my desk with my 3 32" screens.
With Apple Vision, I can have my 3 32" screen outside. Or on the road. Or in the office when I drop in for a day. Or anywhere else I may go. It will be a huge boost in productivity and definitely worth the price.
That is the killer feature for me -- portability of my most productive setup.