OK, a friend of mine, speaking from his experience, suggested trying 25 ga 5/8" needles for injecting. He claims to use them with no pain and easier to hold steady. We are both pretty lean. My glutes have little fat. Anyway I started this week and did 1.25ml of TPP / NPP blend in my left glute. Well - its still sore as hell and has a small knot. Right glute - shot wed. not as bad but sore. I figured the needle was too short and ordered some 1.5" @ 25 ga for the glute. My question - I'm due for another and wanted to use the 5/8" for a quad inject. What do you think? I def. gonna wait for the 1.5 before attempting another glute, plus my a** needs time to recover! No fever, maybe a small amounty of noticable redness on the left side, not hot to the touch. I follow very sanitary procedures. Any experience would be appreciated. Thanks!