If you like to wait in all eternity, then yes. IDL without irradiance caching is going to be painfully slow and even worse with IDL quality set that high and shading rate that low.

Try it out for yourself, those settings are going to be very slow and the gain in quality will be barely noticeable, if at all.

"What should this render setting be" is a bit like asking "how much salt should I put on my food?". Too little is not going to taste great, too much isn't tasty either. The right amount is where it's at, and there is no amount of salt that's equally right all dishes.

If there were one-size-fits all render settings, there wouldn't be a render settings dialog.