Rabbiofberlin: Rav Ruderman’s p’sak was b’davke Pepsi; perhaps because in the 60’s, that was the chamar of the Yeshiva.
In truth I have to hold off what I said about my tea. I know tea is different than coffee in that it’s considered colored water and water of course cannot be chamar medina, but it’s possible tea with sugar is different; so for the time being I retract my tea comment.
And havdalla needs a certain shiur to be drunk so that leaves out hot tea which can only be sipped. And do you serve tea or coffee to guests that is not hot? European Yidden used to drink very hot drinks, so no problem with the shiur at one time , but can/do Americans drink very hot drinks?