Start with what the room has to do
A meeting room needs acoustic separation and a door that closes properly. A finance team needs privacy and a place to put a lock. A corridor needs light without turning into a tunnel. Those three briefs produce three different partition details, even when the drawings look similar.
So the useful first question is not "framed or frameless" — it is what happens in the room, who else is on the floor, and what the ceiling and floor can carry.
Framed: the default for a reason
Framed aluminium partitions carry their structure in the frame, which means the glass can be thinner, the panels can be larger, and doors hang from something designed to take the weight. They also give you a place to put a head channel that lands on structure rather than on plasterboard, and a base detail that survives a floor that is not level.
Most commercial fitouts end up here because it is the cheapest way to get a full-height, acoustically sensible wall that will still be straight in five years.
Frameless: less metal, more discipline
Frameless glazing puts the structure into the glass and the fittings, which looks better and forgives less. It needs a floor and ceiling that are actually parallel, and it needs the door hardware to be right, because there is no frame to hide a hinge in.
It also costs more per square metre than framed glazing, not because the glass is special but because the setting out and the fixings are unforgiving. Worth it where the sight lines matter; wasteful in a back-of-house corridor.
Demountable: for tenancies that move
A demountable system is designed to be taken down and rebuilt, which changes the detail everywhere: how panels lock together, how the head is trimmed, how services are handled. If a tenancy is a three-year proposition, demountable can be the difference between an asset and a skip. If it is a ten-year home, it usually buys nothing.
The details that decide whether it feels right
Manifestation — the markings on the glass — is not decoration. It is what stops people walking into a panel that looks like an opening, and it is required on large glazed areas. Where it goes and how much of it there is changes how the room feels as much as how safe it is.
The other one is the door. A glass partition with a badly hung door reads as cheap no matter how good the glass is: closers that drift, gaps at the head, and a latch that needs a shove.