it really does vary
however generaly from wat ive seen stacking different compounds is almost essential if you want to be competitive
just think about it this way
if your on stage, and the guy next to you is using 2000mgs of gear, how much are you going to use?
would you stand on stage knowing the guys your going against are twice as enhanced as you? or would you likely up the mgs in order to stay competitive?
diet,training and of course genetics are always going to be important factors, however the unfortunate trueth is you are very unlikely to ever beat someone who is using twice the amount of substances as you if there training diet and genetics are just as good as yours
im not saying you need to use boat loads of gear and substances, im just pointing out alot of other guys do
if you can beat them using less, then good on you, but your never really going to know wat the guy next to you is using or taking,
and becoz of this, many guys will increase there substance use becoz they think the guy next to them is using alot more then they are
ive seen guys on 2grams of gear beaten by guys on 500mgs, then ive seen natural guys who look alot better then big juicers,
but then ive seen guys destroyed in comps, (despite they were geneticaly gifted), becoz the guy next to them who carried average genetics was using alot more juice.
i think as you begin to compete you will realise and begin to see what other guys are using, aswell as realise whether or not you have the genetics to be competive
its at that point you can decide what and how much your willing to do,
untill then play it safe, and use wat u consider appropriate