The "best" type of mouse sensor depends on personal preferences and the intended use of the mouse. However, currently, the most advanced and popular types of mouse sensors are Optical and Laser sensors.
Optical sensors use an LED light to detect movement and are generally considered to be more accurate than older mechanical sensors. They also have lower latency and can work on more surfaces than a mechanical sensor.
Laser sensors, on the other hand, use a laser diode to track movement and can be even more precise than optical sensors. They can also work on a wider range of surfaces, including some that optical sensors cannot.
Both types of sensors have their pros and cons, but both are very capable and will provide an excellent experience for most users. Ultimately, it is a matter of personal preference and how the mouse will be used.