If you enjoy mast I am sure you would love primo.I’ve never really had a thick head of hair, started getting thin on top towards the back in my mid 20’s....that said, in the past couple years I’ve used Mast on and off, at doses of 600, wk at times and I’ve never seen any noticeable hair loss. I’m now in my early 40’s, just FYI. I LOVE Mast...you’ve probably heard this before, but it gives you an alpha male, sex freak type of feeling.