Stunning using SC armour is not worth it.
Assuming you get 4 hats in an hour playing fastsc, you gain 66k in bonus xp. However, in that same hour of playing sc, 66k bonus xp in terms of regular stuns is only 200k gp in runes. You could kill green dragons for an hour and get 500-800k depending on CB level and spot instead of playing sc and then just buy more runes. SC hat stunning is really only recommended if you don't want to stun for as long, but if you want that you could just try an alternative method of mage training.
This guide also doesn't mention superheating at all, which is arguably better than high-alching in many ways other than portability and attention level required.
Agreed with the SC armor but Its not my decision to wether ppl use it or not, Im just showing the their options. And ok fine, if you feel superheating is better than High alching, ill add it later. I just always felt other ways are better.