Matching finishes across brands
Brushed nickel from one maker and brushed nickel from another are not the same color, and neither are two matte blacks or two brushed golds. The names describe a family rather than a specification, and the difference is invisible in photographs and obvious on a wall.
That is the practical case for buying a system. Every visible piece is made by one maker to one finish specification, so the head, the handheld, the valve trim and the diverter agree with each other. Assembling the same set from three suppliers is where bathroom projects most often end up with a near match nobody is happy with.
What a shower system includes
Most of these are complete sets: a rain head with its arm, a valve and trim, a handheld on a hose, and a diverter to send water to one or the other. Some are supplied as the head alone, for replacing a head on an existing valve, and a few pair a shower head with a matching basin faucet.
Which of those a project needs depends on what is already in the wall. Replacing a whole shower means a system with its valve; replacing a tired head on a working valve means the head on its own, and the finish then has to be matched to what stays.
Rain head sizes
The heads here come at eight, twelve and sixteen inches across. That figure is the face of the head rather than anything about the flow, and it changes the experience more than the specification suggests.
A small head concentrates water in a column; a large one spreads the same flow over a wider area, which feels softer and covers more of the body at once. The size is a visual decision as much as a physical one, since a sixteen inch face reads as a deliberate centerpiece above the shower in a way an eight inch head does not.
Chrome, nickel, black and gold
Chrome and brushed nickel are the two that sit quietly in a bathroom, rather than announcing themselves: chrome is bright and reflective, nickel warmer and softer, and the two show water differently, which is most of what separates them in daily use.
Matte black and brushed gold are decisions, not defaults. They make the shower part of the design of the room, which is why they are usually chosen first and the rest of the bathroom is brought to them.
Wall or ceiling
A rain head reaches its position either on an arm from the wall or on a drop from the ceiling, and the arm is what most systems here supply. The arm keeps the pipework in the wall and sets the head at an angle; a ceiling drop puts it directly overhead and gives the cleaner line.
The difference in use is where you stand. On an arm the water falls slightly forward of the wall, which suits an enclosure you step into; on a ceiling drop it falls straight down, which is what puts you under it, not in front of it. Which is possible depends on the ceiling and on where pipework can run.
Where it sits in the bathroom
The shower is the largest piece of visible metalwork in most bathrooms, which is why the finish chosen here tends to set what the basin and the bath then follow.
If the shower floor is also being decided, the stone shower bases range covers solid stone trays, and the shower niches and benches page covers what goes into the walls before the tiling.