@brucemobile I have been using it for about two months now. The first couple of weeks take some getting used to. At the beginning, my wife gave me the shot because the idea of putting a needle into your penis is tough to process. After a week I took over and it was not bad at all.
I know they say to do a quick jab, but I will share what works for me. I use my ED pump first so I have a girth and firmness to work with. I find my spot, set the needle, and ease it in slowly until that first pinch. I don't rush it. Once you get past the first pinch, it really is not a big deal.
I do not press the plunger until the needle is all the way in. I press the medication in slowly and pull the needle out slowly. This has worked great for me. No pain and no burning.
The only problem I had early on was with the starting dose. I was getting three hour erections and that did hurt. Now my erection lasts less than an hour which is perfect.
Everyone reacts a little differently, so give yourself some time. For me, it has been a huge improvement compared to using a VED for sex. I will be using Trimix from here on out.