Kate Taylor/Business Insider

Burger King's Impossible Whopper is set to take over America. But, can it compete with the real thing?

In late April, Burger King announced plans to roll out the plant-based Impossible Whopper nationally, after a short test in St. Louis.

Restaurant Brands International CEO José Cil told Business Insider on Wednesday that the test sparked positive response more quickly than the chain anticipated, with both new and loyal customers ordering the Impossible Whopper.

"We're not doing this for a quick pop," Cil said. "We think this is a new category that we can build on for the long haul. We think that plant-based burgers and other products will continue to be part of our business for the long term."

In late April, Cil told investors that he found it "really difficult to distinguish between the Impossible Whopper and the original Whopper." With the chain hoping to win over loyal customers and meat eaters with the new menu item, the similarities between the original and the Impossible Whopper are a major selling point for Burger King.

This week, Business Insider decided to put Cil's review to the test at Restaurant Brands International's Investor Day in New York City. The company was serving both the Impossible Whopper and the original Whopper, so we decided to try each.

Here is how the Impossible Whopper actually measures up to the real thing:

At first glance, a veteran Burger King customer could tell the difference between the Impossible Whopper and the original Whopper.

Side by side, it is clear that the original has a more mulchy, uneven texture, while the Impossible Whopper is more smooth and uniform — a common tell in plant-based burgers.

In terms of size and toppings, however, the two burgers are remarkably similar. Had I simply started devouring my burger instead of taking a peek inside the patty first, I may not have noticed the difference.

Before testing the Impossible Whopper, I decided it was wise to revisit the original.

The Whopper is a fast-food industry icon, distinguishing itself from other chains' signature burgers with its wide and flat patty, as well as its char-grilled preparation.

The patty has a slightly watery umami flavor, which is nicely cut by the pickles and onion.

The Whopper's meaty aftertaste — coupled with an oniony tang — lingers long after the burger is complete.

Having reestablished the Whopper's flavor profile firmly in my mind, I turned my attention to the Impossible Whopper.

If I did not realize that the Impossible Whopper was a plant-based burger, I would not have guessed it from my first bite. It tastes like a "real" burger.

The Impossible Whopper replicated the Whopper's char, down to the grill marks on the burger's patty.

However, there are clear differences between the Impossible Whopper and the real thing.

The Impossible Whopper has a nuttier flavor, compared to the original's mulchy meatiness.

In terms of texture, the original Whopper is lumpier and chewier. The Impossible Whopper's patty features sharp, browned edges in a way that would be impossible to replicate in a meat-based burger.

The original Whopper's flavor is also simply stronger than that of the Impossible Whopper.

While the beef patty's aftertaste lingers, the plant-based patty blends into the burger's toppings.

However, the differences should not negate the tastiness of the Impossible Whopper. It is certainly distinguishable from the original Whopper — but it isn't necessarily the lesser burger.

The Impossible Whopper has a more subtle flavor that impressively replicates the experience of eating a meat-based burger. It feels like less of a gut-punch than many fast-food burgers.

In fact, I only finished one of the two burger halves — and the leftovers were from the original Whopper.

Whopper loyalists may want to stick with the original burger, but for people craving an environmentally friendly option, the Impossible Whopper is a solid choice.

We tried Burger King\'s plant-based Impossible Whopper next to the original - here\'s how they actually compare