I've used the Boss OS-2 extensively, and I find the blend control quite effective. It allows you to mix the overdrive and distortion smoothly, providing a wide range of tones that can be tailored to suit various musical styles. Even at higher settings, it maintains clarity without becoming muddy, which is a significant plus.
In terms of compatibility with other pedals, the OS-2 performs well in a diverse pedalboard setup. It doesn't overpower other effects but instead complements them nicely, especially in a live setting. To procure the best out of it, I recommend starting with moderate settings on both the overdrive and distortion to find a sweet spot before tweaking further based on your specific needs and the rest of your rig.