Ive only used my quad's & Ive used different sizes, but for shooting 2cc's or more at one time instead of sitting there for 15Min's, i started using 20G by 1"
A lot smoother/faster coming out, but I'm thinking on my next cycle I'm going to go down a gauge or two just because of the frequent shots ill be doing & for how long! I'm curious to do shoulders/delts