Definately will purchase again.
More productive workouts (feel stronger for longer), recovery is noticeably better, fat loss is better - only change I made was addition of these and noticed more visible fat loss.
Only 1 complaint (nitpicking) is that the pills are a little dry and hard to swallow - I regularly swallow 5-6 fish oil capsules in one mouthful but more than 2 of these and they get stuck.
Only downside I've noticed (and it's a user issue, not a product issue) is that if I don't get a decent sleep (less than ~6 hours), I feel worse than I normally would getting that much sleep, it's an effort to drag myself up.
If I have a good sleep - I wake up easier and more refreshed.