Well, it is simple.
Output - 50 eu/t Efficiency - 2.5, heat balance +5 (water cooling). I think, it can run through 8 cycles without overheating. And interesting: Instead of cooling period, you can run it with only three uranium cells! just replace the fourth one with the cooling cell and heat balance becomes -10! However, efficiency would be 2.33. output 35 eu/t
And the next one. "The Elements of Harmony". Water cooled Mk.I-O Efficiency - 2.33 Seems like heat balance is perfect (+/- 0), but not sure about heat distribution. Can somepony check it out?