Dear Corret
Wish you a nice day.
1. The price difference: copper is higher 10%-15% than stainless.
2. Brite Beer Tank is also called serving tank or conditioning tank. We add the carbonation stone in fermenter as a unitank.
In terms of the function, brite beer tank is equivalent to unitank. It makes the beer bright.
Looking forward to your reply.
Kindest regards.
Ada