In fact, with the right strains, and by NOT topping, you can get some huge chunk motherfing colas. I did on 12/12. A World of Seedss White Rhino X Mazar i Sharif made the chunkiest damned colas of great smelling bud. From their Medical Collection it is a wonder for 2 spine patients. We love it and it is my grown (MMJ legal) daughter's favorite over the last year. I continue it in my DWC using 18/6 and then 12/12 in my old set ways.
Also a G13 Labs OG 13 (their proprietary OG Kush) and a Reserva Privada Kandy Kush (OG Kush X Train Wreck). Damn that OG 13 rocked it good!!!! Killer bud that smells like you're sniffing & smoking Lemon Pledge. 1 hit buzz for sure!!! The Kandy Kush was the third fave here last year. All of these did very well on 12/12. A Dinafem Blue Widow was not quite as worth it yield wise but the smoke was most excellent.
For a really inexperienced grower I think 12/12 would work very well and is very cheap to get into for obvious reasons.