So having had short, Asian eyelashes all my life, I really wanted a chance to grow them so I could "complete" my look with mascara.
I decided on fLash (or Flash Lash) as it was the cheapest option compared to RevitaLash and other alternatives. I bought mine for $40 plus post from Once It.
I have been using it regularly for a month and a half, and I can say that there definitely has been results, though not dramatically so. My eyelashes are slightly longer (about 0.5mm), thicker and they now curl upwards. However, the growth seems to have stopped, so I believe my eyelashes might have reached their maximum length with this product. People with longer eyelashes might have better results.
I believe you get about 2ml (which is a 3 month supply), however, I'm not sure how much is left (the tube is opaque) and I apply it to both my top and bottom lashline. Occasionally, I do feel a bit of a slight burn and itchiness but it passes quickly.
I have also noticed my eyelashes are stronger and don't fall out as easily.
Overall, it is a good product and I believe it does work.
I have been using this for about 2 years now and I love it. When you use this for the first time - you must use it once EVERY SINGLE DAY. You do not need much product at all but you must use it every day for 6 weeks. It will get to the point when you think "this stuff doesn't work!" and bang on 6 weeks you will have amazing, long thick lashes. Once you have your lashes at the length you want you use a small amount of serum a couple of times a week. I still get comments on how long my lashes are - which is great as mine are naturally very short.
Tips: Be patient - it really did take the full 6-7 weeks for me but its worth it.