Looking at the FAQ section of Integra website, it appears that the product was originally developed for use with cannabis and is only offered in 55% and 62% RH varieties which is the optimal range for that product. I'm guessing it was later marketed for other products such as cigars as well. It also states that it is arrived at by using a "salt free" combination of plant based glycerin and water to achieve the desired humidity. This is more than likely because Boveda has a patent on using salts to obtain the desired humidity levels.
My only concern here is the glycerin and water combination. Isn't that what we used to use in conjunction with green foam in our humidors back in the day? I guess if it is made with purified water and contained in the pack it is going to be OK but it still makes me a little leery. After looking on Amazon and noticing that they are almost exactly the same price (Boveda is actually a little cheaper on the 67 gram packs) I think that I will stay with what I know and has worked for me for the past 5+ years.