To determine if a peripheral features good build quality, one must look beyond the design & ergonomics, and open up said item and look inside. I said it time and again, premium looking peripherals end-up using cheap or poor-quality insides, and that’s usually their downfall.
Taking the M8-610 apart is not a difficult task, quite the contrary. Once the four screws hidden under the PTFE pads are removed, the topside simply comes off since there are no clamps to hold everything together.
Genius has delivered on an interior build quality that is at the very least matching if not better than that of some premium-built gaming mice. Left & Right click both feature OMRON D2FC-F-7N switches rated at 20 million clicks. Under the scroll wheel there's another OMRON switch, though this one is rated only at 5 million clicks. Meanwhile on the top PCB, you have two Huano Red switches rated at 300.000 clicks for Back & Forward buttons, while the DPI-switch is another D2FC-F-7N (strange, but I won't complain, it's a great switch rarely used for buttons that don't see this much attention).
The Scorpion's brain is the NXP LPC11U35F, a 32-bit, 50Mhz Cortex-M0 MCU, with 64Kb on-chip flash programmable memory, and 10KB SRAM.
Lastly, as expected, the laser sensor used is a Pixart ADNS9800, previously known as AVAGO ADNS9800SE, able to reach 8200DPI, which still has some inconsistencies that can't really be ironed out. Unlike the PMW3310 IR-LED optical sensor, employed by recent optical gaming mice, the sensor is riddled with inconsistent acceleration issues. If you're interested in precision, it's very difficult to get a proper response with it.
Overall, the interior build quality is great. The use of switches is nothing short of great, the PCB is clean and neatly soldered, and uses a capable MCU.