Here is another review from a site I trust a lot. They do very nice in depth reviews, in both the real world and a controlled environment.
https://www.dpreview.com/reviews/google-pixel-xl-camera-review/10
They say to leave HDR+ on as well, but give some pointers around RAW capture. Overall, another very positive review with the following conclusion.
Overall Conclusion
If your smartphone buying decisions tend to be based on camera performance and features, 2016 has made things even more complicated. In the past you could simply pick the phone that offered the image output that was most to your liking. Now you have to make your mind up about dual-camera modules and if any of their features would be beneficial to your style of mobile photography.
The Google Pixel XL does not offer variable focal length, nor can its lens blur mode compete with the versions in most dual-cam equipped cameras. However, in terms of image quality the Pixel XL is an easy pick. Thanks to its excellent HDR+ mode that can be left activated at all times, it captures class-leading image quality across all light levels. Throw in an excellent QHD-display, premium materials and build quality, good battery life and the attractive design and straightforward operation of Google's pure Android 7 Nougat operating system and you've got yourself a package that should keep even the most demanding mobile photographers happy.
Features & Operation
The Pixel XL camera app has been designed with easy operation in mind and offers all you need for swift and efficient shooting in Auto mode. Those who want more manual control or shoot DNG Raw files have to look for alternatives in the Google Play Store, though. The Pixel hardware supports those functions but they have not been implemented in the stock camera app.
In terms of special modes the Pixel offers an unusually large selection of panorama modes, including Google's 360 degree Photo Sphere. Those modes allow for interesting ways of capturing your surroundings but the image output tends to show noticeably more stitching errors and artifacts than the panorama modes on some direct competitors. Lens blur mode is not on par with its equivalents on the Apple iPhone 7 Plus or Huawei P9 either. On the plus side, the 120fps/1080p and 240fps/720p slo-motion video modes can produce very appealing footage. Unfortunately, the only way to export an edited file is uploading it to Google Photos, though.
Image Quality
The Pixel XL is capable of capturing decent smartphone image quality in its standard mode but the device really comes into its own when HDR+ is activated. Thanks to clever multi-frame technology, the Pixel's HDR+ images show better dynamic range than most competitors in bright light. In lower light both detail and the management of image noise are excellent for a smartphone camera.
The Pixel camera is capable of capturing usable images in light conditions that not too long ago some DSLRs would have struggled with. The really good news is that, thanks to the powerful Snapdragon 821 processor HDR+ can now be on by default. Compared to standard mode the processing delay is hardly noticeable and won't be a problem in almost any shooting situation.
Overall, the Pixel currently leads the smartphone pack in terms of image quality. (Emphasis is mine)
The Final Word
The Google Pixel XL is a well-rounded premium smartphone and currently offers the best image quality of all smartphone cameras. If you can live without the additional flexibility of the "tele"-lens in the iPhone 7 Plus dual-camera or the super-wide-angle in the LG G5, the Pixel XL is an obvious choice. If you don't like its rather large dimension, the sister model Pixel offers the same camera specifications in a smaller package with a 5" 1080p display.