Despite the name potentially suggesting otherwise, the M3S Varun isn't just a sized-down M3. While the curvature of the sides, degree to which the front and back flare out, and shape of the main buttons geometrically are a match, the hump is positioned towards the back on the M3S Varun, whereas it is centered on the M3. Relative to the rest of the body, the hump is also slightly taller, resulting in the M3S Varun sloping down more steeply towards the front. While not a drastic change, coupled with the smaller size, the M3S Varun feels distinctly different in hand. Another thing to note is that even though the comfort grooves on the main buttons are similarly deep as on the M3, the buttons being narrower to begin with has the grooves feel more noticeable on the M3S Varun.
As for grip styles, I'd say the M3S Varun mostly suits claw grip. It is a medium-sized mouse with a moderately pronounced hump, which should make it generally suit most hand sizes. For reference, my hands are 19 cm long and 10 cm wide, and I found the M3S Varun comfortable in claw grip.
Dimensions
This table includes the dimensions of the Darmoshark M3S Varun and several other ambidextrous mice. "Front height" denotes the distance between the base and main buttons. Measurements with two decimals have been taken with a caliper, while those with one decimal have been taken with a ruler. For a full list of all measurements taken, please refer to this sheet compiled by an esteemed community member.
Darmoshark M3S Varun Dimensions
M3S Varun
XM2we
Atlantis
Hati-S Plus ACE
M3
X2
MM712
Base Length
11.3 cm
11.6 cm
11.7 cm
11.0 cm
11.8 cm
11.4 cm
10.9 cm
Length (including overhang)
12.30 cm
12.2 cm
12.33 cm
11.69 cm
12.85 cm
12.02 cm
11.5 cm
Front Height (lowest point)
1.1 cm
0.9 cm
1.1 cm
1.3 cm
1.1 cm
1.1 cm
1.2 cm
Height (highest point)
3.79 cm
3.83 cm
3.80 cm
3.88 cm
3.93 cm
3.74 cm
3.79 cm
Front Width (widest point)
6.01 cm
6.16 cm
6.16 cm
6.12 cm
6.54 cm
6.12 cm
6.04 cm
Back Width (widest point)
6.27 cm
6.49 cm
6.59 cm
6.08 cm
6.53 cm
6.33 cm
6.25 cm
Grip Width (narrowest point)
5.75 cm
6.06 cm
5.96 cm
5.60 cm
6.06 cm
6.02 cm
6.03 cm
Below are some comparison shots with each of the measured mice: