Avarege viz render time ?

[MoonDoggie]

The most important thing is reflection depth. change everything to one. if something has a glossiness of around .7/8 with objects visible in the reflection switch it to 2, and higher switch it to 3. glass is the only thing that needs to be higher (and if there's any amount of glass in my scenes i switch it off entirely and do it as a separate fully reflective pass to add back in post)
If you pre calc the irradiance map/LC with glossy effects switched off and reflection depth on 1 (sometimes i'll use the vmc to switch reflections off entirely) it'll speed it up to a ridiculous degree. I use most of that speed boost to increase the quality significantly though.

Cubicle, you're a genius. My interior scene I rendered last night used to take 3hr 32m. It rendered in 1hr 10m with very little difference in quality. Thank you again. I'm going to finish my script to set these values automatically to help out everyone soon. Thanks again.

[glorybound]

what about the refraction max depth? Just as important?

[MoonDoggie]

I don't have many refractive shaders in my scene, so I didn't touch it personally, just reflection.

[Dariusz Makowski (Dadal)]

It depends what for you are using ur refractions... but yea they bit important. On another side you can speed up ur render using in GI LC > user LC for glossy reflections + using Interpolation on less important surfaces...