I bought this to help our new kitten hazel to be accepted by our resident cat harry, I'm not sure if it was coincidence or the plug in but the next day they were getting on just fine.
While I can't say for sure it was the plug in I'm sure it didn't have a negative effect and my cats are happy 😃 so I'm happy!
Before I used the plug in Harry would hiss at Hazel but he wasn't physically aggressive, once I used the plug in he completely stopped hissing and became more interested in playing with her.
Hazel did then go on to hiss (I think it was a shock for Harry to suddenly want to play) but it's been about three weeks now and I think Hazel is just a bit vocal when playing.
She definitely want to play as she initiates it but she is quick to play the abused little sister act when Harry pins her (and licks her)
hahaha.

Working very well for my anxious dog, and my cats are very chilled!

This worked within hours. I have a cat who is bored of shutdown as she loves people and none coming in to the house due to shielding. She goes out to anyone nearby and not a lot of those either. She has no off switch! Loves her brother but torments him and he retaliates then so does she. Three vet trips for chewed legs and infections and others I’ve treated at home in three months. Vets recommended the plug in and it worked. Then after 3 weeks, when no cats about, turned it off and forgot about it. One week later he’s tried to take her face off. Vet no. 4 for a gaping hole right through to her mouth. I’ve had to accept the smell as nearly £100 a visit was becoming a bit much! Arranging neighbours to take one or other in wasn’t ideal either. Been plugged back in for nearly two weeks and all is peaceful again.

Seems to be a very good product, dog seems a lot more chilled during the day.
In terms of how long it lasts i would say about 25 days on non stop.
The scent isn't overpowering so you hardly even notice it. Something we will invest in again.

Works great for our anxious cat, stops him over grooming.

My poor dog is very anxious and a nightmare in the car. Whimpers and shakes and very sick within 5mins of a journey. Used this and she was definitely less stressed. We stopped after 1hr of our journey for her to have a break then carried on for the last hour of our journey. As we stopped, she was sick but I think she's just travel sick. It did reduce her stress levels though and 2 days later when we travelled the 2hrs back, she actually slept a lot of the journey and no vomitting at all.
Not so fussed on the smell but can put up with it for her.