Red Cups or Styrofoam?

[oakley]

I messed up and need to buy some cups. I'm ready to start potting up.
I like to recycle and have a ton of red cups from a party but the are a different style and very fragile...the ones with the ridges. Seems they are using less material and have ridges to strengthen them. Also not as tall as the big reds.
I've used the big styrofoam and really like them. And could recycle a bit for packing material and crushed into the bottom of big pots. Still hate buying them.

Maybe my red ones with ridges were stepped on, who knows.
I use the restaurant bus-boy trays and both styles fit really well. Maybe the styrofoam a bit better as they sort of stick to each other.

Is it just personal preference? or is one really better than the other.