La Croix, you better watch your back because you just got some serious competition. This week, The Costco Connoisseur came across a brand new line of Costco sparkling water, and the flavors are suspiciously familiar to those of its competitor. 

Kirkland Signature's (Costco's home brand) calorie-free, sodium-free, sweetener-free sparkling water is flavored with lemon, lime, and grapefruit, which happen to be three of La Croix's most popular flavors.

In a side by side taste test, The Costco Connoisseur found "both the KS lemon sparkling water and lime sparkling water tasted exactly the same respectively as the La Croix lemon and lime sparkling waters." She also notes that the KS grapefruit has a "familiar hint of grapefruit taste, [but] it was a slightly different grapefruit flavor than what I was used to from the La Croix pamplemousse sparkling water."

She found that the biggest difference between the two brands had nothing to do with the taste, but with the bubbles. She claims that KS sparkling waters were bubblier and had more carbonation than La Croix waters. 

So, even though there isn't that big of a difference between the drinks, their prices seem to say otherwise. "At $7.49 for a 32-pack, the KS sparkling water is just $.23 per can, compared to $.33 per can for the regularly priced $7.99, 24-pack of La Croix sparkling waters sold at Costco," The Costco Connoisseur reports.

This comes out to be a 33% savings in comparison to a regularly priced La Croix 24-pack, or a 15% savings when compared to the La Croix sale price at Costco.

#SpoonTip: Prices may vary between warehouse locations.

In the end, it's up to you to decide which sparkling water is best for you. The only way to find out is to head to the store and taste test both brands. So, grab your keys and prepare to chug a lot of carbonated water.