I confirm than 150 ppi for a A0 or even a A1 poster is plenty enough.

300 ppi for an A4 is really common.
But you don't watch a A0 poster at the same distance as you look at an A4.
So actually with the 150 ppi on an A0 you have a relative much better resolution than 300 ppi on an A4.
To understand ...

Hello guys,

I'm also considering very seriously about Octane.
In order to jump, I don't worry that much about sss. (It has to be there of course) I do need it a lot.

But there was nothing said about hair and particles. (If I'm not wrong)
Is there any possibility to simply use maya's hair system ...