Sensor and Performance

This mouse uses the PixArt 3360, the current top-of-the-line sensor. It performs just as well as you would expect it to.

To showcase its performance, I tested the mouse at various CPI steps in MouseTester by moving it across my mousepad's surface area as quickly as possible. The result is excellent, showing no signs of tracking loss. Judging by my test results with other PixArt 3360 mice I'd say it's fast enough for any human to never worry about hitting malfunctioning speeds, especially with the weight you have to throw around here. I only tested the RAT 8 on a soft pad, but I tested other PixArt 3360 mice on various surfaces, and they never gave me any trouble.

CPI Accuracy

The CPI steps are also very close to the proclaimed value set in the software. There usually is a slight variance to CPI with all mice (i.e. you set 400 CPI, but it actually is somewhere between 390-410 CPI); however, the more accurate the better. I test these because in the past, certain mice had a very high divergence at their upper end, where 6000 CPI would really be 4900 CPI, for example. So the CPI accuracy you see below is actually very good and most of all consistent.

Cursor Behavior

I drew lines in Paint using the pencil tool to see if there are any problems with the cursor's path (for example: jittering, skipping, severe angle snapping, etc.). A bad result would have zig-zagging instead of smooth lines. The waves in the straight lines I drew are on purpose; they test angle snapping of which there seems to be none.


As a verdict, cursor tracking is near perfect.

Another part of how the cursor behaves has to do with the lift-off distance of a mouse, which determines at which height the mouse stops tracking movement over a surface. For the RAT 8, it can be set in the software to either "calibrated", 2 mm, or 3 mm. Calibrated is similar to what Logitech did with their surface tuning; it sets the lift-off distance very low. The higher lift-off distance values are useful if you use a surface where tracking is difficult. My experience has shown that the PixArt 3360 tracks well on all gaming surfaces, but the calibrated option might help ensure stable tracking for someone who uses a desk with a reflective surface, or another difficult material.

Speed-related Accuracy Variance

With this test, I show how accurately the sensor reports movement at different speeds. You can see me move the mouse at varying speeds from a starting position and back again, at a different speed. In the top-right corner is the showpos command in the source engine. The second row shows the viewing angle, of which my point of reference is mainly the second one, the x-axis angle. With a script, I set my viewing angle to 0 0 0 at the start. After every swipe back to my starting position, I record the deviation from the starting position.

There is obviously some degree of error here due to me doing this test manually because I lack a test bench that is able to limit movement to the x-axis. But as I have done the same test with a variety of different mice and sensors, it's possible to compare. In this test, the angular displacements were 1.03, 2.74, 1.1, 3.05, 3.77, 3.2, 1.91, 3.62, 1.83, which is a good result; however, I've seen better with PixArt 3360 mice. It's not a big issue, though.