Image quality and DR for Phase One backs.

[Soocom1]

So I have found that there are a number of Phase One backs that are well within my reach at this point.
Included in that bunch are a couple of Leaf Aptus as well, and I am wondering who has experience with them and what the total image quality, DR, and any other aspects between them.
I am crossed to getting the P20 at a 36x36 but would like the larger P30 or P45 but I also want the ISO 50. (for my purposes.)

Please let me know or even post examples of any images from them.

Same with the Leaf.

Thank you.