I have a cheap plastic-like one on my porch from Sam's Club. It's huge. I put a cinder block in it & haven't had any issues with it. It doesn't have a pedestal, though. That might make a difference. I put rocks in the bottom of all of my smaller pots, too. It's better for drainage, adds weight, and saves on soil needed.
I had one like that, and it was cement. There was no way that thing was blowing over. Hell, I thought my dad was going to have a hernia moving that damn thing.