Try the 12/12 from seed. Over at Open Grow (??) site, have seen a bunch of nice grows with Sannies sativas 12/12 from seed.
On the Sannies site, he even has specific plants / m2 for 12/12 from seed, 1 week veg then 12/12, etc.
He does them SoG from seed. Not sure if you want to do that or not, but worth checking out.