Which Container is better Sun or Rackable?

I had an interesting call with an investment firm who wanted to discuss Data Center Containers.  He asked a question which one has a better container Sun or Rackable?

I told them it's too early in the container game to declare who the winner is.

Jokingly then I said Rackable, because it's bigger, and hey part of this is marketing and you see a 40 foot ice cube next to a Sun 20 foot project blackbox which one is more impressive.  He chuckled at the comment.

After a bit more thought. I do think Rackable picked a better initial build out with 40 foot vs. the 20 foot Sun Box.

If you are going to go with containers are you going to take small steps? Or go for it with a 40 footer.  Note Microsoft's references to CBlox being 40 feet.  There is no mention of 20 foot containers.

This flies in the face of the idea of over provisioning, and getting more than you need, but marketing means giving what people they want to buy, not what is logical for them.