Tried an Impossible Burger for the first time the other day. In a burger with lots of condiments and toppings, it was OK, but not something I'd order again. When I took a bite of it by itself, it tasted like cat food.
Since there are so many positive reviews, I wonder if it just wasn't prepared correctly? The restaurant had only started serving it a few days earlier.
I tried one at Umami Burger and left with the same general impression as you. It was bland by itself, saved by copious melted cheese Umami Burger serves it with, and did not have any of the nice pink associated with medium-rare. I guess it's comparable to a fast food burger, but does not seem like anything I'd want to repeat. The sugars and vegetable oils listed on the ingredients list make me wonder if the whole thing is even healthy.
Since there are so many positive reviews, I wonder if it just wasn't prepared correctly? The restaurant had only started serving it a few days earlier.