There's a whole thread on preworkouts
here - many different opinions, good stuff.
What's available to you and what do you prefer? [rhetorical]
I prefer 10 mg Adderall, 5 mg Aricept, and a cup of coffee. Gets me through resistance training and/or cardio early in the morning.
Good point about sleep. For anyone else reading this, either find a way to train earlier in the day or get used to training with less stimulants if they fuck up your sleep.
The added intensity to your training isn't worth it imo. Poor sleep is a gainz killer.