I have not tried these personally; but do hear what happens to crack addicts and junkies from time to time. Just one time is such a simple but powerful line indeed!

To me, taking substance to produce content feels like a tainting your natural rhythm i.e. the one that comes normally to you. I do understand from your post that these can possibly give you an altogether different flow with the work you do; but at what cost to your health and finance?

You will need that drug to reproduce that similar content every time. Missing out the negative aspects of any drug, even something as basic as caffeine and thinking that their intake will help focus on one job and one job only (be it writing or dancing or whatever) is surely not how things work.

We should be in a position to partake everyday distractions, deal with relations and still come up with great content. I am not sure if any of the substances will cope better for your body than the natural rhythm that time and experience sets up for it!