"This page does not address what I imagine to be one of the first major questions that a newbie would face - plane vs. copter? What are the pros and cons of each, for different applications? I thought I had seen such a discussion, but…"
"You need a short baseline (distance between base and rover)
You need a very good quality antenna, one that is designed to reject multipath
Horizontal accuracy is typically twice as good as vertical accuracy. For example, if H=1cm, V=2cm