I love delts. I usally Pin rear delts about an 1-2" above tricep insertion. Practically painless goin in as it is not a very tense muscle, such as the thigh.
Godspeed

that's what I use for just about every site. and I'll go up to 3cc's in my delts. however my delts are not average sized, so plz don't try this unless your sporting cannon balls.

I use 25 5/8th" on my meaty delts..anything else is too long.. I also never put more than 1 ML of anything in my delts.. that PIP is a bitch or said son of one...

I'll use a 23g but it isn't pleasant.

I got some 26g 5/8 recently and they worked well, but stand by for me is 25g 1inch

That will work fine. I personally use 25g 1in and sometimes 5/8in and have never had problems.