I've been working out for more than a decade and had totally plateaued at the gym in terms of my lifting max.
I heard about Turk and figured I'd give it a shot. I purchased the HC Gains version of Turk because a competitor was always out of stock. I have now been on Turk for about 6 weeks. I have to say that I think this stuff really does work. My pre-Turk bench press max was 220lbs. I am now benching 270lbs (3-4 reps). I've also found that my squat has improved too - but I've been focusing more on a deeper squat versus extra weight. Other than the performance increases, I also noticed that my recovery time has been faster so I can still target the same muscle group twice a week if I want.
In terms of dosage, I started taking 500mg a day but later increased to 1000mg and even experimented at one point with 2000mg a day.