longer cycle or short?

Seeing that arnold ran some long cycles just curious to know what would yield better quality results,which would be better?
10 weeks of 600mg testen a week
or 20 weeks of 300mg testen a week
wont a long cycle like that shut you down pretty bad ....what pct would you do?

You will have to experiment.
Neither of those will do anything for me, but thats me.
Now Add some Deca/NPP into that and i would really only see results in 11-12 weeks. So for me, up to now, with the cycles i've done i can put my money on a 20 week Deca/Testen cycle at 600-900 Test, 700 Deca. That would be on the money for ME.
You might respond really well to 600 testen for 10 weeks - who knows.

I find that with long cycles I reach a bit of a plateau where gains stop coming in as easy... Even if I up my cals. I think theres a point in the cycle where you just gotta call it quits, but no doubt this set point is different for everyone.

As normal I use one of my close friends as an example and he is one of SA's top bodybuilders. Last year he was on gear for 6 months because of the local shows and a show abroad, he changed his gear every 5 weeks and believe me it worked. I would say that the more active pros in the world also has to be on juice for months on end so they need to change it up often.