If I can take clones from my flowering plants at like day 12 or 14, that means I have about 50 days, give or take, to have those clones rooted and vegged a little. I don't even need them vegged really, I usually put my clones right into the 6 1000 watt room and run 18/6 under the same HPS's they will flower under(I change bulbs every 2 rounds). So I wouldn't have any extra power bill really, ill keep them under my t5's until i harvest and can move them into the big room. Which actually is perfect because im going to pot up with my clones next time instead of putting the clones rooted in rockwool cubes straight into my 5 gallon pots which i did this time and wasnt as productive, took a little while for the roots to fill up. So the approximately 2 - 3 weeks of veg time theyll have after rooting, giving 21-28 days to root, will allow me to have them fill in a 1 gallon container, then a 2 or 3 gallon container, and then into the 5's. The t5's hardly cost anything to run. And i'll still get 4 harvests a year which is all i need.