Top at that age are you crazy fool ,leave them they look fine has they are if any topping to be done do it during the flowering phase,follow the main stem to the very top of the plant then snip yhe new growth this will give you 2 buds instead of one it's easy if you see someone do it watch i grow cronic on you tube .there is no reason to top these nicely formed babys get the light has close has you dare put your hand under if it is too hot for your hand its too hot for your plants.this will stop your plant been leggy i could understand topping if they were leggy but they look fine.