Buying accessories as a set solves the problem nobody anticipates: that a dispenser, a dish and a tumbler bought separately over six months will not quite match, even in the same finish, because they were made in different runs.
These are designed together. The proportions relate, the metal is from one batch, and they sit on a counter as a group rather than as three objects that happen to be nearby.
The Tonino Lamborghini sets are the exclusive ones, and the Ruffle sets are finished in hand applied gold or silver leaf, which means each piece carries slight variation in the leafing. That is the nature of the technique rather than a flaw.
A set is also the cheapest way to change the character of a bathroom without touching anything plumbed. If the room is fine but tired, this is where to start.