Has anyone tried using a flask to drink during the morning at work, if so was it horrible?

Not a flask, but make a cup sometimes and either put it in a paper or ceramic cup and put it in the car. It tastes different than if I have it at home, but not unpleasant.

I have an Aladdin thermal mug with a really good lid. I put 3 shots in it and top up with hot water. I usually only start drinking it after an hour or so, tastes fine.

I’ve only had stovetop coffee in a flask, which was also fine, but I drink mine black, no sugar

It’s not bad but it suffers like most coffees from sitting for ages.

Sometimes make and sweeten espressos the night before, chill and then take a flask of iced coffee

I’ve done it…… tastes fine (latte content though).