I haven't used one, we make all of ours from 4x4 posts. Dan's right, there's nothing to making one with just basic tools. The one from Alumapanel may or may not come with the ground stake. If it does the stake itself is pretty slick, it works as it's own post driver to install it making it easy for real estate agents to stick one up themselves.
I wouldn't recommend the vinyl one for a permanent sign, if it needs to last make your own. It's funny, looking at your picture it looks like somebody just skipped the stake and buried the bottom of the post in the ground.