I use 23g 1" for my delts. The first delt inject I had ever done turned pink and actually had tendrils for about 8-9 days before the coloring and marks completely subsided; no infection, I simply put a lot of product into my delt...especially for a first shot. The second delt inject had no marking whatsoever. The only thing you can notice is a tiny spot where you insert the needle for a few hours, for me at least...I'd say go for it and see how you react. I'm assuming you never poked your delt before.