Use my iPad more than my Mac, specially when I'm on the road. And now that I'm carrying my AVP, I'm starting to use it more and more.
On Tuesday I had to review plans for a construction site. My Macbook and iPad displays were not the best tools for this.
I was able to see the full plans in full size, measure distance points and plan best routes for network cabling runs and write some needed annotations on these. No eyestrain, no need to zoom one section at a time: That's priceless.
Also, looking at the Topology map of a large network, nothing can display it better than the AVP.
If the tool is not for you, don't buy it. Not everybody have an air compressor at home, because not everybody is going to put it to good use. But this doesn't mean that those who don't have it are going to criticize does who do have it.