The cup is fine. Drinks won't stay cold forever if you're outside in the heat, but it does what it's supposed to do.
The Dubby powder though? That's another story entirely. No jitters. Straight energy and focus for at least half the day, easily.
The Shaker is a good quality, the graphic on the Shaker is really cool! My only criticism is that a larger graphic would make the Shaker twice as cool. There is alot of clear space on the cup
