I had a lot of fun running a 1212 from seed tent a few year ago (only 2x3 in size and alongside my 4x
. Started in solo cups but preferred 1ltr square pots so I could cram them in (about 40 plants before sexing). It became obvious that some strains really took to 1212 and put out and some seemed to struggle to get going.
Yield was strain dependent, some would put out an Oz in 1ltr pot or just under, others over half and some you'd only just make double figures. It was worth the time and electric though.
One thing to consider if you're pheno hunting is how you keep the plant around. You can top (think
@Opie1971 may have done this and flowered in larger pots? Hope your well if you read this mate) or reveg at the end of flower (leave lower buds, pot up if you can, 24 hour light for a week then 18/6, shoots will appear within a couple of weeks out the bud).
Post up if you go down this route, its something I'm thinking of doing again later on in the year.