I've used this bar on two different targets, and I can see the results.
My first target was a previous relationship. He was stubborn, so it helped us kind of communicate. (This was over 2 years ago.)
My current/most recent target and I have had a great time with this. We have a very chill relationship and communication doesn't always come easily to us. Regardless of this, he's been naturally responsive to this potion.
We both have been. We communicate more consistently, peacefully and beautifully. I think this works best with people who have a mutual interest in a long term connection or companionship, regardless of relationship status.