SMD strip is a row of individual emitters on a flexible board. COB strip spreads the phosphor across a continuous surface, so the lit result is a line rather than a series of points. At any distance behind a deep diffuser the two look similar; close to a shallow one they do not.

That makes the choice a function of the installation, not of quality. A strip buried in a channel with a 20mm diffuser can be SMD; the same strip in a headliner cove where the viewer sees it directly will show dotting, and the complaint will arrive as a workmanship complaint rather than a component one.

Silicone coated versions matter more in vehicles and boats than in buildings. Condensation in a cabin and pressure washing in a service body both find bare strip, and the failure shows as dead segments where moisture reached a solder joint rather than as a whole run going out.

Addressable RGB is a third category rather than a variant. It needs a controller and a stable supply, and it is usually specified with a switch panel and a fused harness because it draws differently from static strip.