The differences are subtle with small dosages, and there might be a substantial placebo effect.

But as a personal summary, LSD makes me smile and I feel like a better person. On it, I find myself preferring good life choices and productivity. Amphetamine gives me endless focus and nervousness-flavored mental energy, similar to too much coffee. As a bonus: Modafinil makes me almost angrily opposed to distraction and slacking off.