Indeed, those look great! Have seen some pics on Google showing plants in Big Gulp soda cups. Not much soil. If you tiered, (your square container on top of Maxwell House container), tap root would have more room to grow. I've noticed the circumference of container often shows how much branching will occur. They should start showing puberty signs any day now. Will be interesting to see how these pan out. I'd be tempted to pinch off allowing for 2 colas being in such cramped quarters.