Too late to help the OP but hopefully useful for others, as I was searching for the same information a month ago:
I ordered 3 copies of a 42pp photo book from Presto for Christmas gifts this year. I am running Photos in High Sierra and used the tools built into Photos and then exported the PDF and uploaded it to Presto. The books cost more because I couldn't find any coupons/discounts, but it was worth it to me not to have to fuss with third-party plugins (~$55/book for hardcover 8.5x11 with dust jacket, extra 22 pages over the basic 20pp book, sales tax, and priority shipping).
I am quite happy with the book and the recipients were VERY happy and touched to receive the gift. The books feel high quality and make an impressive gift. Presto gave me dire warnings about backlit photos coming out too dark, but I ignored them and did no adjustments at all, and it was fine (although all my full page photos are well-lit landscape photos, the backlit faces are only half-page or quarter-page shots). Binding is solid, and the paper feels nice--when I had a good photo, it printed quite well (my blue skies and beach shots are lovely--i had some blown-out skies that are of course still blown-out). The dust jacket is nice heavy paper, heavier than Apple's was--I enjoy using the dust jacket flaps to present the story and the flaps came out well. The picture wrap on the front/back/spine of the book itself is also nice. The Presto logo is not large and includes a link where people could reorder a copy of the book (I think the link is optional but useful)--do use the tools to move the logo to the bottom of the back cover as it would be more obnoxious at the top, in my view. I used the paper and settings that Presto recommended to "make it like Apple's"--I forget what those were exactly.
The only issues--on one of the 3 copies the dust jacket was not folded quite correctly and since it is heavy-duty plastic-coated paper, I'm having a hard time getting it to take a different fold, so it sits a bit wonky on the book (but time on my bookshelf should fix that--I would have worked on fixing it more if gifting that copy). USPS caused more delay than expected: I uploaded it on 10 Dec (I think), and Presto said Priority Mail through USPS would be fine but for some reason while Presto shipped it around 12/17 and USPS originally told me 12/19 for arrival it actually did not arrive until 12/21.
I would happily use Presto again--if I weren't under time pressure, I might try one of the plug-ins/extensions to see how it goes, but I will probably continue to pay the price rather than figure out a new process. I had previously used Apple and My Publisher to do 8.5x11 hardcovers and this book fits in well with those. Using webservices doesn't fit with my workflow despite the temptation of 50-60-70% off coupons--I really want to use a bookmaker inside Photos itself.
(Side comment--for other photo gifts, would also recommend Target Photo if in US--the stone coasters let you upload 4 different images and the ornaments let you do 1 photo on each side, and I was happy with how both products looked and felt in the hand.)
