I must confess that I prefer medium length books.
But please don't think that my book choice depends on the number of pages or a book size. No, no, no. But I noticed that the longer the book is, the longer I read it and the more distracted I get. And they are big and heavy, they don't fit into my bag, and the progress on my ereader is sometimes demotivating (So many hours left? Why am I such a slow reader?!?).
Too short novels aren't good either because as soon as I engage into the plot it's already a finish line. That's why the medium sounds reasonable, let's say around 300 - 350/400 pages. But maybe it's just me?
Today The Huffington Post shared 5 long books worth reading so maybe I'll give them a second chance: