This all breaks down to how you want your plant to grow and how many tops you would like . If you have lots of space height and width wise you can top them and let them heal and repeat this process till you have one GIANT plant or you can top it a few times and let it grow and have more then one plant . When it comes to training like this , topping , FIMMING , LST its all about preferences so for example a training method that you really enjoy and that works really well for you may not be ideal for another grower , it's all about needs and goals . You also wanna factor in the amount of "healing" time that it takes topping a plant to gain extra "tops" is great but most of the time people use this method in order to help control the height and canopy of a plant . Over all I'd say you got lots of space and some nice healthy plants you could top them many many many times if you liked or just do it once again its all about preferences . I hope this information helps you on your quests to becoming a grow master :) -Happy Growing!