It has decent compatibility and good speed. Furthermore, I challenge anyone to find a PSX emulator with fewer lines of code with competitive speed and accuracy. To my knowledge, this is by far the simplest such implementation, and is able to do this by taking advantage of Javascript JIT compilation.
For example, this PSX emulator: https://github.com/kootstra-rene/enge-js
It has decent compatibility and good speed. Furthermore, I challenge anyone to find a PSX emulator with fewer lines of code with competitive speed and accuracy. To my knowledge, this is by far the simplest such implementation, and is able to do this by taking advantage of Javascript JIT compilation.