I have the same question.
Using headphones and comparing the Legacy reverbs, it seems that the Room reverb is stereo. With a setting of Decay 0, Pre-Delay 0, and Mix around 50%, I get a wide, but instant stereo room ambience.
However, when I try to record that in my daw, the effect turns too wet. It's effect of widening stereo image sounds cheap once recorded.
So, what is the best practice of recording a wet signal with reverb?