i think you should do 12/12 from seed for the following reasons and them only:
1) interested in seeing what will happen
2) space issues
3) you want a constant field of plants to just throw them in or other plants are in 12/12 and you are starting more
4) youre using low powered cfls
also to answer those questions
hoping an ounce to two off both together
we have thrown in seedlings with flowering plants in my friends grow before... they got about 12-24 inches tall and yeilded 1/4 to around 3 ounces per plant... the actual amount has depended on light and genetics more then anything, indica and sativa to me have no difference 12/12 from seed
also 12/12 from seed doesn't speed down growing like a lot of people think!!!, if it takes 8-9 weeks in flower, and lets say you are going 12/12 from seed with cfl your grow will take 13-15 weeks!!!
just so you know, if youre doing it because of timing, its not the best reason
I just wanted you to know, the reason I am being so critical is because I was thinking about trying this myself, and I'm trying to glean as much info as I can. I should also explain that the main reason I only see this method as 'necessary' when growing tall sativas is because they get so tall, too tall for my grow area. have a 6 foot tall grow area, so basically I have to keep my plants under 4 feet (unless outdoors). I can veg an indica for a long time and flower it and I will still have enough vertical space without having to worry about it getting too tall or close to the light. With a Sativa, however, I may run into space issues. That is why I made the distinction. Anyway, I don't think my Hawaiian Snow will fit in there, as they get so tall (like 6 or 7 feet). That is too tall, especially with room for lighting on top and the pot and soil below. Thats why I am thinking about this.
I see the inherent value in just being able to throw a couple seeds in at any time and get a perpetual harvest, I also can see why It may be necessary with some strains, because for me space will soon be an issue. so I will probably flower my Hawaiian Snow right from the start or with only one week of veg.
However, the problem for me is that, while it may not take more time, it also doesn't take any less time either. I had always thought of this method as something people would do to cut down on growing time, but as the turnaround is 3-4 months either way, I don't see any reason why you shouldn't veg for a month with most strains. If you are restricted by CFL's, then I can see the value there as well. However, I have a 600w digital ballast that takes both MH and HPS without having to use a conversion bulb, so I am not constrained in that way. If it is gonna take the same amount of time, personally I think it would be better to Veg for a little while. Just my personal opinion. Your reasons are pretty sound, especially for your situation.
For me, I may throw a couple feminized seedlings during this next flowering cycle. My next grow is Hawaiian Snow, and It will still be in the middle of the Summer when they are done flowering. Since next grow is gonna be 12/12 from really young (I might veg them for a week or 2 outside before bringing them in to the flowering chamber). The feminized seeds should finish up within a couple weeks of that since they will have been going so long anyway. I will try this out, but mainly as a space-filler. Those yeilds sound alright for the size, and I saw your yummy buds, so I might try it with a couple plants. What size pot do you normally use for one of these grows?