If I'm not mistaken, I think preliminary observations from people with the P30+ may be in some other threads on this forum.
As it happens, I took the P30+ out for a quick spin today with a friend of mine (note: yes, I'm still considering selling the P30+ and no, I didn't drop it or anything when playing around today!). As a preliminary matter, the only criticism I have thus far is that the auto white balance is less than spectacular for daylight shots. This was also the case with my P30. (Although I mostly shot the P30 in the studio with strobes, so white balance was much more controlled and therefore spot-on). Also, while I was shooting, the shots looked underexposed on the LCD so, rather than trusting my in-camera meter, I opened up by about 1/3 of a stop so the shots looked correct on the LCD. Lo and behold, I open them in C1 and they're all overexposed by almost exactly 1/3 of a stop. Lesson: If I'm going to rely on the screen for exposure feedback (no, I wasn't using the histogram; I generally don't because I find it distracting for this type of shooting), I need to adjust the screen brightness.
The attached JPEG was processed quickly in Capture One (I'm sure I coul optimize it with more time). No adjustments other than levels to compensate for my overexposure. Shot with a Contax 645 w. 140mm lens at 2.8. I purposefully shot at ISO 400 even though it was bright enough outside to use 100, because I wanted to see the ISO 400 quality. To my eye, the ISO 400 is a *substantial* improvement over the P30; I considered ISO 400 on the P30 to be useable in a pinch, but certainly not on a regular basis. By contrast, I'd use ISO 400 on the P30+ without much reservation. In the attached shot, there's a bit of noise visible in the shadows, but it seems minimal and not really an issue for most shooting.
No flash or reflectors, just natural light. (This shot could have used a bit of a reflector from below to lighten up the darkness udner the eyes. But I can fix it in post.).
Conclusion: if someone doesn't buy this from me soon, I'm keeping it.

(Sorry about the large image size, but I though people would prefer to see a large image).
And yeah, I kind of think she looks like Angelina Jolie. If you can afford a MF digital back, she's too young for you. :-) (And me too).
If you can't photograph young girls without attatching jokey sexual conotations your probably best off not shooting young girls.