Finally I have both copies of the book "A Portrait of the Alhambra", that I made both in Apple's Aperture and in Blurb's Booksmart. The results are very interesting. Firstly the Aperture version is slightly larger at 28cm x 21.6cm, compared to the Blurb version which is 24.1cm x 20.3cm. I ordered the Blurb book in their "Premium paper", which is noticeably thicker than the Apple version. The Apple paper is still good though and both cover and pages have a nice silky finish while the Blurb book has a glossy cover and silky pages.
The slightly bigger Apple version
The quality of the actual printing is very similar, and apart from one rather important difference, may simply be a matter of personal preference. I found the Apple photo prints to have slightly more reddish/yellowish tones, which on most of the photos gave quite a pleasing effect.
Pages from the Blurb version
However, on the one black and white photo in the book, this was not what I wanted and in this respect the rendition of colours in the Blurb book is much better. The other photo that also gave a very different result in the Apple book, was one of the Alhambra at night, where the sky has a brownish tone, whereas in the Blurb book it is completely black. I personally think that the Apple version is perhaps closer to my original photo, but the Blurb print is far more pleasing.
So which one is better? Overall, I think I prefer the Blurb book, even though there are some aspects of the Apple book that I really like. What makes the decision easy in the end is the difference in price, the Apple book being considerably more expensive.
The whole Blurb book can be previewed and purchased here.