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.