I shoot both ways. I’ve done IM Only, SubQ Only, gone back and forth, IM one day, SubQ the other. And I don’t notice any difference with how I feel. The only thing is IM in the shoulder stings a tiny bit, but the pain is from breaking the skin. Once broken, I don’t feel any pain as the needle glides into the muscle. SubQ in the glute doesn’t hurt at all.
Also depends on HOW much you are injecting. If I’m doing a full 1cc, then I don’t want to put it in my delt as it leaves a lump. So I limit the arm to .5. Lastly, as someone else mentioned about lumps, if I inject SubQ into my abs area, I’m left with a lump.