This is my 13th week of using Latisse... around 8 weeks I did notice extra length but not enough to spend $120... I haven't noticed much more volume or length since that 8th week period... and its not even enough where anyone could tell the difference.
I do recommend using an eyeliner brush to put on the product rather than the big brushes they give you. I put latisse on every night for almost 13 weeks and Im still on my first bottle, so it does save a lot of the product. I also did notice some darkening of my eyelids (near where I apply the product) not enough to really bother me bc I would apply eyeliner there anyway. My two friends have had the same results as me.