Are they tart or sour

When it comes to sensory perception, Sourness and Tartness are considered the same and referring to the level of acidity in a food or drink. Some differentiate tartness as being sourness specific to tartaric acids and tannins present in wines. Revel Berry acidity would be mostly coming from Citric acid and then it should not be “tart” but more “sour”.

it has a little sweetness to it- but no it's not sweet tea. I can't remember exactly, but there is sugar in the drink. I don't like sweet tea, I drink only regular and I love this stuff! All the flavors are great.

What's the wiehgt for the case/package?

The weight for a case of 12 15.5oz cans is 13.1lbs

The sugar content on these seems high. Can you speak to that?

Thank you for reaching out! Guayaki Yerba Mate offers a variety of flavors and sugar contents for our customers. If you are looking for canned yerba mate with less sugar, we recommend our 15.5oz Tropical Uprising cans with half the calories of our other 15.5oz cans. We also offer low-sugar options with our 12oz Sparkling Lima Limon and Sparkling Blackberry Mint. Have a great day! -The Guayaki Yerba Mate Team