Damn how long does it take to inject cuz I use 23g to pin and it still takes a second lolYup... all in 1!
You're actually the 2nd person to ask this question today.
Just use a different pin to draw. Because if you puncture 3 different vials with a needle, then put that needle in your skin... its gonna hurt! You are dulling the hell out of it every time.
I use 21g to draw and 27g to pin.
But yeah you can put 5 different compounds in a barrel, that doesn't matter