Which is faster space port building, planet or constructor?

[Vardis]

I've seen a constructor get stuck because it was a few units short on helium, but it had enough helium to put the extra 25 or 50 or whatever in the cargo hold of the station for future upgrades. But you're right. Most cases are when the constructor didn't bring enough with it to finish the job, because it went to a spot that didn't have a stockpile of whatever was needed (usually a new space port), rather than picking up stuff from my nearby well stocked home world.