I discovered the following with in game testing. Can someone else confirm this? It seems too crazy to be true. I'm probably wrong, I hope I am. T2 of any factory builds T1 units just as fast as 3 T1 factories. T2 demands 4x the metal as a single T1 factory. Also discovered through in game testing, the build power is also stated in the UI, and can be seen with the Unit Database mod via PAMM. Sooo.... T2 produces units 3x faster, but costs 4x as much metal... in other words, 15 metal per second disappear into thin air when you use T2 factories. It would be more metal efficient and just as energy efficient to just use T1 factories - and that's not even going into the greater metal and real estate costs of T2.