Hi I'm after trying out mk-677 as a standalone running for 12weeks at 10/20mg Im currently in my early 40s and have trained for a few years in crossfit I'm mostly after better recovery more & endurance my question is I have looked at the following companies

Sarms4u
Peaquebodynutrition
Imuscle
Pumpingiron
Samms. Co.Uk
I was wondering if enyone has used any of these company's products as I know quality can very