Topping is reliable.....fimming not very reliable and MUCH more stressful for the plant.
After extensive experiments with topping vs fimming, I will never fim again and only ever use "normal" topping now, due to excessive recovery time when fimming and great difficulty getting fmming to work reliably/successfully too.
I would suggest just sticking to normal topping, your photoperiod plant won't mind it either.