I'd say go for it. However, don't bring the roll into the prom with you. There will be a shit ton of police on the way in and people will get searched. I guarantee that getting arrested and charged with a felony will ruin your night. If you are saving it for the after party, find a way to have access to it without bringing it with you into the prom.
In general I would tend to shy away from the consumption of narcotics at a prom.
Good advise, except ecstasy is about as far away from a narcotic as you can get. Narcotics are drugs that put you to sleep, and good luck sleeping while rolling. I agree with what you said about taking the risk though. I just get nit picky when people refer to stimulants as narcotics. Ever wonder why people with
narcolepsy get prescribed adderall to stay awake?
Limp dick... Prom... Just no
Ya, consider this when you decide to roll or not. You know how your equipment works better than any of us. However, if you're date is rolling too, you'll both have a shit load of fun whether your dick works or not. If she isn't rolling though, she might be a little annoyed.
Also, if I were you, I'd skip the coke and go easy on the booze. You're not going to need more stimulation, and rolling is just flat out more fun than drinking. A couple drinks is fine, but the more you drink, the more you'll just feel drunk which is kinda defeating the purpose of rolling. Also, both of those will only make your dick less functional.
Finally, as Bsiren said, test your rolls or at least look it up on pillreports. You don't want to get piped on prom night. Either look it up or find someone else that has used the exact same roll. "quad stacked" means jack shit. It's just the dealer trying to sell it. Hopefully it's actually good, but I wouldn't want to risk prom night on a potentially shitty roll.