When Impossible was new and only available in burger format at a small number of partner restaurants, I ventured out to SF to try two of them. I concluded that it can make for a genuinely convincing substitute, but the key is preparing it with a sleight of hand to misdirect from the noticeable imitation texture and flavor. Those early burgers were made with thin patties, with flavorful burger sauces and toppings.
As Impossible expanded beyond their launch partners, they lost their control over the consumer experience. I think many restaurants now serve wretched Impossible Burgers because they just substitute a beef patty and don't try to accommodate the differences.
If you are savoring it as part of a taste test, it will never fool you; the first impression isn't the takeaway. If beef is not the focal point of the dish, as in their Impossible Mapo Tofu recipe (https://impossiblefoods.com/recipes/impossible-mapo-tofu) or a chili or something, it can slot in pretty well. They are nowhere near substitutes for ribeye steak or smoked brisket.