The real question is has anyone in this thread or that anyone knows been on mk for at least a year or more?
I'm about 2-3 weeks shy of 12 months straight right now. I can't say I've noticed anything extraordinary at all. Maybe a slight improvement in skin in the last couple months. It definitely helped me sleep better and deeper for the first while until that wore off (10mg). When I bumped the dose up to 20mg, the sleep improved again. That seems to have worn off sometime in the last couple of months. This is likely just an adaptation to a "state". If I were to bump the dose to 30mg, I am quite confident I would see that boost in sleep quality again.
Since moving to a 5 on/2 off protocol a few months ago, I believe I've seen an improvement in my joints. I don't think 365 days a year supplementation with MK-677 is for everybody, or even wise for that matter. Coincidentally, the improvement in my skin (although modest) started around the same time I changed from everyday dosing to 5 days a week.
The best thing I've noticed about MK-677 is that it is much easier for me to maintain a higher weight over the past year. Even during times where I wasn't able to train because of work or injury. I will also say that gains come on easier on cycle when stacking MK-677 with SARMs or steroids.
Sadly, I'm on my last bottle of OL Gharine and so it looks like my run might be coming to an end. I'm on the hunt to find another bottle to take me threw until the new year. At that point in time, I'm going to cease use. It'll be interesting to see what happens in the first few weeks when I finally come off.