I've been using it for 2 weeks and don't discern a difference yet, but it might be too soon to tell. So I can't tell you if it works or doesn't work, please buy at your own discretion.
Would be nice if the base was slightly heavier so it doesn't tip over easily, but otherwise, simple to use, good design.
I use tretinoin as well, and I was afraid the Booster would make the skin absorb too much and my skin would peel even more, but weirdly there was no difference, which is good I guess.
I also wish the EMS shot would start at 350microamps instead of 465, because even at 465, it is uncomfortable on my teeth (and I don't have sensitive teeth!). I am also afraid of long-term ATP depletion if I go over 500 on my face (or experience too much muscle-twitching) as I've read some scientific papers on this issue. I am thinking of buying a lower microcurrent tool to use daily, and use the EMS shot more sparingly.
For recommendation, I am neutral (can only choose yes or no in the box though, so I just ticked yes). I think there is no harm trying, price is reasonable, design is simple to use.