Charizard worth dust?

Hi everyone,

I've seen a lot of people post about Fire Spin and Overheat and how its so amazing. I know he's not ideal anymore, but whenever i need a Fire mon, I've found that my 91iv 2550+cp Bite Fire Blast Arcanine can more than easily knock out the defending Pokemon. So, is there any reason to power up my 93iv 1522cp Charizard with Fire Spin Overheat? I heard people use them against Blissey but I already have a 2800+ C DP Machamp and Confusion Future Sight Alakazam.