Sure, take it. You'll die 10-30 years younger than the average life expectancy; your final years will be marked by crippling disease: movement disorders, diabetes, heart failure...
Risperdal doesn't "guarantee" lucid dreams, but they may happen -- along with terrifying sleep paralysis that will make you dread sleeping. Your sleep will be very light, and you'll wake up several times each night, usually paralyzed.
You'll also have dizziness and difficulty breathing when you get up -- from your bed, for example, or from a crouching position --, sleepiness throughout the day, you may start lactating even if you're a boy (because of increased prolactin levels), decreased libido (if you masturbate once a day, you'll masturbate every 3-4 days), erectile dysfunction, a decreased ability to think (you'll have difficulty coming up with stuff to say in a conversation)... It's not a fun drug and it will slowly kill you, literally.
But despite this, take it! It may give you a couple of amusing lucid dreams that you can tell your friends.