I had it twice a while back I think. It was surprisingly better than I expected, and I didn't notice much of a difference. That said, I rather have real meat. But it's definitely a good innovation, especially in the distant future when meat or food in general will probably become more scarce.
Curious to try the Impossible Whopper as well, since there's a Burger King a few blocks down from me. But I never like the whopper in the first place. So I likely will not like it regardless.
The truth is strictly what the ones in power perceives it to be.
Enjoy any good things, even the little and menial ones, as you will never know what impending distresses could descend upon you in a moment.