one's more like a band-aid and the other goes to the root of the problem and solves it long-term. the gen 6 is what will solve your problem (see my review on the product page on how to use it). that's not to say that the tightening lift botanical serum is bad, it just gives you more "right now" (but temporary, unless you use it for a few months) results. that being said, i'm certain you’ll be thrilled with the immediate results of the gen 6, too. and by the way, you CAN use it under makeup, just make sure you give it about 10 minutes to fully absorb (I highly recommend using it w/ the toner to accommodate this!). the gen 6 is a little more expensive, but in my opinion, it's also a better value & lasts longer. if you're really serious about results, technically, you could use them both, even on the same day, but the gen 6 goes first, wait AT LEAST the 10 minutes, and then follow w/ the serum (go lightly!) and then your makeup.
answered 5 years ago