I share the positive take on those needles as my favorite option. The warehouse store isn't an option for me without a card. A sizable medical supply spot sits roughly ten miles away so deliveries arrive fast. Nothing else gets used for shots. Extras that showed up get repurposed to release air or handed off to pals. Pens only came to mind not long ago yet now I'm completely hooked. Just a few reusable models plus some single-use ones were tried first since interest was uncertain and the result felt ideal. More of the newer versions arrived over the weekend with plans to add another style soon. The sound and response of the mechanism draw me in along with the process of loading cartridges.
I find that the bulk of my peptide supplies arrive in ten milligram quantities, causing them to run out fast, which leads me to mix fresh batches every week. NAD along with GHK stand out because their supplies endure much longer. For the GHK, I prefer allowing it to remain undisturbed no less than a quarter hour. It wouldn't make sense to have all the material in the syringe waiting around that long or up to half an hour ahead of the injection. NAD behaves the same way. Because of this I can't find a good reason to purchase one right now.