It was $2.49 for one (the same price as their regular Quesarito), but I received this one courtesy of Taco Bell. It's also available with chicken ($2.99) or steak ($3.29).
While there's the same familiar beef, rice, sour cream, and cheese mix found in a lot of Taco Bell's burritos (both limited-time and regular menu-versions), the new Sriracha sauce puts its own stamp on the proceedings with a dominating blend of spicy, tangy, garlicky, and creamy.
But with the second half, the Sriracha was much more complementary and I could better taste the other components. The heat level was likewise toned down (no drink required).
Of the two halves, I prefer the second half since I prefer a more balanced burrito. If you miss lava sauce and it was the only thing you found remotely spicy (i.e. you regularly eat, and possibly breathe, fire), you might want to ask them for extra Sriracha in your Quesarito (or whatever else you might order).
Overall, I enjoyed Taco Bell's Sriracha Quesarito quite a bit; more so than the regular Quesarito, which I felt didn't do enough to differentiate itself from what came before. Basically, I enjoyed the extra flavor Taco Bell's creamy version of Sriracha added. It captured the flavor of the original pretty well, while fleshing it out to fit with Taco Bell ingredients.
Nutritional Info - Taco Bell Sriracha Quesarito (269g)
Calories - 650 (from Fat - 290)
Fat - 32g (Saturated Fat - 12g)
Sodium - 1720mg
Carbs - 68g (Sugar - 7g)
Protein - 22g