I am just reading the new Hamilton Void book, Abyss Beyond Dreams, the Void trilogy fourth volume. These new SF books are so colossal even trilogies expand. The actual books are huge (in size and scope). I can’t take it on holiday, or put in pocket of bag for travel.
I also have loads of the old ‘pulp’ SF books, which are all of a much smaller size, typically 100 pages on thin paper, in a small format. These are very portable and I sometimes take one to read on the tube. They all have lurid images in bright colours so some things don’t change!

Check this out:
See some classic Science fiction covers here on Barnes and Noble >

50s SF covers and stories