disagree as much as you want.

but blurbs print quality is best described at "decent".
even scott kelby has no nicer words for it.
the adobe lightroom forum has a thread where most users have only complains for blurb.
at least the last time i looked it was mostly negativ comments.
i have done 3 books from blurb, books where i did not care about the print quality that much.
for best quality i use a local (german) company that produces much better books.
they print no logo on your book (something you have to pay extra for when using blurb).
they don“t convert to cmyk, they print (nearly) full sRGB colors.
the pages have an UV coating.