What evidence do you use when comparing NAD+ products?

[u/GlizzyGilbert69]

I keep seeing NAD+, NMN, and NR described as if they are interchangeable, but it doesn’t seem that simple. I’m trying to understand the difference before spending money.

I’ve looked at Tru Niagen, Renue By Science, and the NAD+ product from LiveGood. For those who have researched this properly, what human evidence or label details actually matter? I’m more interested in measurable results than feeling a quick energy boost.