I know this isn't AIBU but honestly, it's amazing stuff! My left brow has always been sparser than the right and it had gotten worse in recent years. I was having to tint and fill in my brows almost every week and was seriously considering microblading.
I read a few positive reviews of RapidBrow and though I was sceptical I figured I had nothing to lose in trying it. And WOW! It really works. I have thicker darker brows for the first time in years and don't even have to use brow pencil anymore. In fact I need to get a clear gel just to keep them groomed and in place to avoid the Denis Healey look.
The only downside is that if you stop using it your brows will go back to what they were but I think that's true of all hair loss solutions. And no I don't work for RapidBrow, I just think it's genuinely great!