It does, but then find me a Linux user who doesn't dual-boot into Windoze for desktop apps. This way, you save one reboot. I wonder, however, how stable this will be...
If by 30 you mean 20 gigs then, yes. Also, 20 gigs on a very decent 256GB SSD costs around $6.40. I don't know how much your hourly wage is, but the time Visual Studio saves me compared to other development platforms makes up for that money pretty quickly.
That might be true; I had a slightly tainted image of VS when I had to use it three years ago, and after everything I needed was installed, I only had like a gig left (this was on a weak, underpowered netbook, admittedly).
In retrospect it's not entirely VS's fault, though I just found it amusing how quickly it ate through my storage when Vim only takes like 90 megs.