Very difficult to acquire these days, and it's a good adaptation of the mini series (both the pilot and the final battle).
As it's quite an old book, the print is pretty small and cramped, but it does get a lot of detail into it.
Well written, and in places it expands on some of the characters that didn't happen in the show, but other parts that I recall seemed to be missing altogether.
If you liked the original 80's TV show then you'll like this. For others it may not be as good but still a great sci fi story in it's own right.