What’s the difference between SMD and COB?

SMD: it is the abbreviation of Surface Mounted Devices, meaning: surface mount device, it is one of the components of SMT (Surface Mount Technology), SMD lamp beads are the bulbs that are encapsulated by this technology.

COB: (chip On board) is fixed on the printed board, because the IC supplier is reducing the output of the QFP (a package of SMT parts) in the LCD control and the production of the related chips. Therefore, in the future products, the traditional SMT mode is gradually replaced. COB lamp beads are the bulbs that are encapsulated by this technology.
MECREE also have COB LED floodlight and SMD LED floodlight.

First model is COB LEDs, which we called GL-FL series, 100W-5000W is availabe. 10°/24°/38°/60°/90°/120°beam angle option.

Second model is SMD LEDs, which we called GL-SFL series, 100W-1200W is available, 30°/60°/90x135° beam angle option.

The advantage of MECREE high power lighting is heat sink, use fins four-dimenisonal cooling, which make junction temperature be controlled around 65℃. As we known, for LED lighting if the junction temperature>70℃, light decay falls quick and affect lifespan.
How do you think about the COB and SMD LEDs?