best drink to get the shakes?

may just be my tolerance honestly.

so, a couple years ago, i was a junior in high school and panera had the charged lemonades. i fucking LOVED those things. i had the unlimited sips membership, i'd get one at 7:30 before class, 2:30 when i got out of school, sometime around 6pm in the middle of my work shift, and occasionally one when i got out of work.

that stuff was like CRACK. it was cold, it was refreshing, and after the second one of the day i'd start shaking from the caffiene. i LOVED it.

now, no more. i've mourned the loss ever since it was discontinued. i average a couple redbulls, an alani, and maybe 2 caffiene pills a day. 600mg-ish, if i had to guess.

has anyone found anything similar to that drink? similar taste, i like the sour of the lemonade, i like the lack of carbonation, and i've found nothing that even comes close to the amount of caffiene in those bad boys. it was SO easy to drink.

the closest i've gotten is dunkin's peach sunshine energy made with lemonade instead of seltzer, but depending on locations, they sometimes refuse to make it for me because it's not technically allowed in their system.