I'm getting one, too.
I'm expecting that in a few years I'll have to replace the poly panels but overall I expect that I'll be happy. We shall both see!!
I am going to follow the advice on that blog you linked to, especially the part about using 4x6 timbers as the foundation instead of just putting the greenhouse directly on the ground. I advise you to do the same!
As for your idea of ordering a different opener each day: don't you have to pay shipping again for each order?