I have been using Trimix for about 6.5 years. I was diagnosed at age 51. It has been the only thing that works. I am using the same dosage as when I started years back (3-4 units). The injection part is still uncomfortable. I was told by my urologist that you can get an auto-injector, whereby you hit a button and it does the work, but I have yet to try. I was also told to use the vacuum pump 1-2 times a week for 15-20 minutes if not using Trimix 2X a week to keep the penis healthy. Maybe this has helped to keep the dosage consistent (?). In summary, I am a fan of Trimix.