I got this stuff as a Christmas present. My brother knows I work out at 5:00AM so he got me some because I mentioned needing some more BCAA Boost and NO Reload from TrueProtein.com (discount code DNT276 if you get there due to this).
I was excited to try a "retail" product because it's something that I would never pay that much for. The ingredient profile looks great for a NO product, but people had some really negative things to say about side effects so I went in hesitantly. I mixed up half the recommended dose for the last few workouts, but I have yet to drink more than 50% of that.
If you do the math, that's only 25% of the effective dose of all the stuff in there, which is probably not enough to accomplice anything. The excessive caffeine is why you have to back off. It's listed at 400mg per serving, but there is a lot of other energy stuff in there. It's enough to really cause nausea and excessive energy...this coming from someone who thinks half a RedLine before a workout is just fine.
All in all, I think it's a great product based on the ingredients and the taste (Grape is awesome, but WAY too sweet). However, you can't take enough of it to get any benefit out of the ingredients that cost money - you get overcome by the basically free caffeine.
Clearly this is meant for people that need to feel something to think a supplement is working. I'd rather they cut back on the caffeine and put in some beta alanine if that's what they're going for.
In the meantime, I'll stick with my BCAA boost/NO Reload with no caffeine from TrueProtein and dose myself with NoDoz so I know exactly how much caffeine I get, but this was a fun experiment and the GNC AMP products have nice packaging, too bad it was garbage.