Aspirate with delts. Not everyone is the same. I have aspirated blood twice in my delt. The first time I simply pushed a little farther and injected, big mistake. I had a gusher, and I started hacking and felt so freaking lightheaded it was pathetic and I was freaking sore for a week! The second time I pulled out, replaced, chose slightly different spot, no problem. One thing is I always nick a vein in my delts so I must have alot of blood vessles in there. So yes, I'd aspirate in delts. You won't die if you don't but I don't ever want to experience the above again - it made me almost want to stop the cycle.