I took my first AlivebyNature NMN yesterday, wow, so normally I would take a Niagen along with a (supposed) Pterostilbene 1000mg and Vit-D3 3000IU with juice first thing in the morning on an empty stomach, this followed with a half teaspoon of L-Glutamine Powder and a half teaspoon of Vit C powder, usually (but not yesterday) a home made fruit and veg smoothy as well.
Normally by the time I leave for work (+/- 1hr) I had a slight Niacin flush, yesterday I followed the same protocol minus the smoothy, about 20 mins later it hit with a bang, the tops of my wrists and back of my neck were suddenly itching, the tops of my legs knees to thighs and my back were positively glowing warm and I had a tingling sensation under my skin, and some slight nausea (not to bad)
Of course I found later that AlivebyNature actually recommend NOT taking it on an empty stomach, so none to blame but myself, this morning I had the Vit C and L-Glutamine earlier as usual with juice, later (about 2hrs) I had some crackers with cheese and then did the Vit D, Pterostilbene 1000mg and the NMN and the effects were much milder, but I do feel it, I'm not a chemist or anything but I would compare Niagen as Petrol and NMN as Rocket fuel
That was one pill of the booster NMN
Also pricing, I bought 3 bottles of 60 caps each and the price was very comparable to their Niagen I think about $155 (135EUR Approx) with shipping to the EU. It's definitely not more expensive.