Taco Bell recently came out with a Grilled Chicken Soft Taco (and a similar burrito) on their Why Pay More menu. As I tried it I thought, this seems just like the Ranchero Chicken Soft Taco, only without the sauce. And about a dollar cheaper. So I went on the handy Taco Bell Nutrition Calculator and discovered that the difference depends on how you compare, and order, the two tacos.
The chart below is the result page from the calculator (I cleared out the non-essential buttons and labels). As you can see in the first two rows the Ranchero Chicken Soft Taco is about 35% bigger. Note, that's weight, and not necessarily all chicken. From what I could tell, they both use the same tortilla. The Grilled Chicken Taco has 70 fewer calories, 6 fewer grams of fat and about 200mg less sodium. I would suspect that also has to do with the lack of sauce. That got me thinking, what would happen if we compared them both without cheese and sauce?
Fresco Style is what Taco Bell calls substituting cheese and sauce with pico de gallo ("Fiesta Salsa"). As you can see from the last two rows in the chart above, the answer seems to be that both tacos get strikingly similar. The Grilled is still bigger, at least partly because it had Fiesta Salsa to begin with. But the calories and fat slide down to equal or almost equal, and the Grilled Taco is within only 80mg striking distance of the Ranchero Taco in terms of sodium. For fast food lovers with a healthier bent, there doesn't seem to be much reason to spend about a dollar extra for the Ranchero Fresco when the Grilled Fresco will get you essentially the same taco experience.
Now you must, if you'll pardon the expression, take all this with a grain of salt. After all, these measurements are in ideal conditions with pre-measured portions in a controlled test kitchen. In the real world of fast food taco assembly, there could end up being very little difference between the feel of these two tacos ordered side by side. Still, adding sub-dollar chicken items is a welcome move and Taco Bell should be commended. It almost makes up for jacking up the price of my beloved Beef Combo burrito. Almost.