Not the best idea, due to the fact they're already your friends, you have moved past that creating comfort and getting to know each other phase. So the effect won't be as accurate as opening a girl whom you've never met. Also because you already know them, you will subconsciously know what they like and act according to that frame. This is counterproductive because every girl is different, especially girls you've just met. You would get better results while testing in various targets from different backgrounds.

Just do day game and test them out on the new girls. What do you have to lose? None. I can only see the advantages. It helps your approach anxiety, improve your inner game, gain more experiences and more importantly, creating new connections everyday.