Why shouldn't I go this route? (AC Roof Delete)

So 600w of panels will likely produce something around 2400w-hr per day.

The unit pulls about 1000w when running, so that gets you around 2.4hr of air/con per day. Slightly more in heating mode. This all assumes a 100% solar/battery system.

With this setup, you can say you have air/con but really other than cooling off during a quick lunch stop, it's not going to work.