I use the scroll, but I would like to try the numbers like Fusious said. Can't tell you how many times I've scrolled my mouse only to have it not switch back to my gun. I've tried the numbers, but my natural instincts will always be the scroll.
I scroll, but itâ€™s oretty unreliable. However, when you use numbers, you have to let go of WASD to switch, removing your mobility. Basically, both methods can get you killed, pros and cons. However my suggestion beats all! https://www.sandboxd.com/posts?thread=6302