If you use it correctly, it works wonders.
The car I have is third-hand, and both previous owners were smokers with closed windows and AC.
Changed the cabin filter and the car still smelled like cigarettes. I used it under the supervision of a technician and now the car smells like I bought it brand new from the dealership.
1st, turn on the AC and the recirculation, let it run for 10 minutes.
2nd, after the 10 minutes are up, switch it to ECO mode, meaning to bring in air from outside for about 5 minutes (it will create some condensation on the windshield, don't be alarmed), clean it, and that's it—the smell in my car truly changed.
*When the ten minutes are up, open the windows; it's not the most pleasant smell.
FOLLOW THESE STEPS AND THAT'S IT

Really terrible, it's nice for the first 20 minutes then it smells like plastic and mustiness, I've had the car open for a week and the smell won't go away, I even changed the cabin filter and nothing

excessive, I followed the instructions faithfully and for 10 days I couldn't use the car it smelled like a badger

Bubblegum scent. The nice smell lasted for a few hours. Now, it's been almost a month and the car smells bad from the "cleaner".

For the issue of disinfection and "cleaning" I can't know if it did the job, unfortunately, the scent in both lemon and bubble gum did not last more than 3 days inside the car and they don't smell very nice. Even though it is the largest in quantity in its category. Obviously, with 2€ you don't expect much. Meguiar's has it for 15€.

I used this product mainly for the annual maintenance of the air conditioning in a relatively new car, with an air conditioner that didn't have any unpleasant odors, minimal usage, and yet I managed to give the cabin a terrible smell of old plastic. As soon as you put it in, it has a nice chewing gum smell, but after a while, it starts to stink. Today is the fourth day with the car constantly open to air it out, and I don't see any improvement. At least someone else shouldn't fall for it