i'm new so, i would really like to hear some opinions from the experts on this question too. i just had my first grow, flowering into 34 days now. i have limited space like you do, and got choices of two different pot sizes. either to grow smaller pots and have twice as many plants, or grow bigger plants with more colas. from what i understand so far, it depends on the strain. i've read that some strains do really good when you top them some don't. i would imagine that most of the strains do much better with topping.

really its up to you to experiment, you can never know what genetics your mother will have unless you go through selection process and choose the best mothers for your specific need. to choose a good mother is very important!

one thing i know is you would have bigger colas with bigger pot size with bigger plants. as of yield, you have to experiment and weight it out in the end.

as turnaround time, well, if you have smaller plants they "supposed" to grow faster with two colas. on the other hand bigger root mass with bigger pots wouldn't take much more time to grow to four colas.
so its all about our own preferences and genetics we choose.

i hope this helps. have fun.