Build Quality

Overall build quality is solid. There is a clear rattle coming from the scroll wheel when shaking the mouse. When applying lateral pressure, no creaking or flexing of the shell can be observed. Activating the side buttons by squeezing the sides is impossible. Lastly, accidental clicks when slamming down the mouse do not occur.

Buttons

Main buttons on the DM7 Switch Duo are very good. There is some pre-travel, but post-travel is low, resulting in a firm and snappy button response. Despite being visually separated from the shell, lateral button movement is minimal and needs to be provoked. Button stiffness is medium. A pair of Kailh GM 8.0 (80 M) switches is used.


Swapping the main button switches is fairly simple. First, the main button piece needs to be removed, which is only possible upon pressing and holding the button at the top. The switch sits in a frame with two handles, which are used to pull the the whole thing out. The switch then can be removed from the frame and a different one inserted. Physically, any 3-pin mechanical switch is compatible with the switch socket, but electrically, there may be incompatible switches. Dream Machines offers Huano (blue shell, white plunger) and Omron D2FC-F-K (50M) (China) switches for separate purchase.


Side buttons are good. The forward button has minimal pre and post-travel, while the back button has low pre and moderate post-travel, and feels significantly mushier than the snappy forward button. The pressure point is almost entirely even across the entirety of these. Button placement is good as actuation is possible rather easily by rolling one's thumb across, but the forward button in particular is small to where it feels flimsy. A set of low-profile switches from Huano (white plunger) is used for these.

At the bottom of the mouse is a single button for cycling through the available CPI steps, which works just fine. A seemingly unbranded tactile switch is used for this one. The slider at the bottom changes between off-state, on-state, and on-state with illumination, and too works fine.

Scroll Wheel

The scroll wheel is decent. Noise levels are high, especially when scrolling up, and tactility is merely average, with the individual steps lacking separation. The encoder comes from F-Switch (brown, pink core) and has a height of 11 mm. The middle (scroll wheel) click requires medium force for actuation. An elevated switch from Huano (red plunger) is used here.

Surface

The DM7 Switch Duo has a slightly rougher, matte surface all over. Grip is fine, and it doesn't attract fingerprints or dirt too much. It is easy to clean, and there are no signs of wear left after doing so. All in all, excellent materials.

Button Sound Test

While the first video demonstrates the default Kailh GM 8.0 switches on either main button, the second video shows a Huano (blue shell, white plunger) switch on the left and an Omron D2FC-F-K (50M) (China) switch on the right one.

Disassembly

Disassembling the DM7 Switch Duo is very easy. The screws are located beneath the front and rear skate. Once those are taken care of, top and bottom shell are readily separated.

The internal design is quite simple. Both the battery and side-button PCB are screwed into the top shell, and both are connected through a 3-pin connector. Everything else sits on the main PCB, which is moderately thick and affixed with two screws, along with several clips. The MCU is a Sino Wealth SH68F1001S.


As for the soldering and general quality of the PCB, I'm unable to find any noteworthy flaws.