Pens have been my thing for 16+ months. I keep 4 V2s, one per peptide (mots, ghk, ta1 and others), and only for daily pokes, never for GLP1 since those vials last 4-6 weeks and I want minimal handling. Zero trouble so far. The pen sweats once it leaves the insulin case, and I had to work out how to handle that. Spend a few months mastering insulin syringes first, then move to pens. A 5ml bulk syringe lets me skip venting.