It is okay to date your best friend. The advantage of dating your best friend is that both of you know each other so well so you don't have to struggle in knowing what the other likes and what ticks them off. The other good thing is that you already have a foundation of friendship and you have built trust between the two of you. However, there are cases where when best friends decide to date, everything between them changes for the worst and they end up being enemies.
Yeah it's ok but think about it when you guys break up you wont be able to talk because it's weird and you won't be best friends again an if you are every one is going to think you still have feelings for him