Lately I’ve had the good fortune to add a few very nice omnibus editions to the Teetering Stack that is my To-Be-Read pile. In looking them over (I won’t actually read any of them until I make a dent in the Partially-Read pile, but that’s another matter), I started thinking that omnibus editions are both a good thing and a bad thing
A good thing…
It’s really handy to have several novels between one set of covers, convenient to have the books in one place. They’ll necessarily be shelved together, and they can’t be inadvertently separated. This is a good thing, you’ll never have the experience of looking for that one title and somehow it’s slid along the shelf, or worse has hopped to another shelf entirely, separated from it’s mates just when you really want to read it, or look at the cover, or check the copyright date, or whatever.
The contents of an omnibus are in some sort of logical order. Usually it’s two or more novels and they are in chronological order as published, which is almost always what I want when I read them. This gives automatic continuity, and there’s no need to take several books off the shelf and compare copyright dates, to discover the earliest, or the next, in a series, which is something we’re all likely to do if we want to read ‘em in order.
Buying an omnibus is almost always less expensive than it would have been to buy the individual books. No, it’s not always true, and it’s not always a lot less, but there is usually some savings. Also, by the time an omnibus becomes available the original books may no longer be available, or not new copies. Omnibus are rarely published until the contents are out of print and there is sufficient demand. That demand may be generated by a film adaptation of one of the books, or a new volume in a series long unavailable, or just some mystical “suddenly these are hot” occurrence. Or a book club may be the publisher.
Many people, especially the ones who fancy themselves Collectors with the capital C, look down their noses at book club editions, but the books clubs have published some pretty handy omnibus volumes over the years, and they often survive the individual books and are cheaper.
Another great thing about omnibus volumes is they usually (and I think should always) come with an introduction. This may be by the author, publisher, another author, a friend or a critic’s cat, but it will have some information about the books collected, the author, and that’s usually both useful and interesting.
Occasionally, the novels in an omnibus edition will have been reviewed and revised by author. If you see this as a good thing, then think of it as the “author’s cut”, a chance for the author to correct those niggling little things that bug him/her, and possibly the reader, whether they be inadvertent mistakes in continuity (the one story house suddenly has an upstairs on page 92) or just something the author always wished had been slightly different, like a proofing/editing mistake that can now be repaired.
There’s certainly much to like about an omnibus volume.
…and a bad thing
However, there’s a down side. For a lot of readers, the book cover is part of the experience, and with an omnibus, you might get one of the covers but usually you get something new and different. That means you don’t get the original covers, and that may be a bummer. It doesn’t seem publishers spend a lot of time (or money) on the graphics with these books. If I wanted, say, some Perry Mason books (which I happen to like a lot), I’d sure rather have the paperbacks with their covers, than a generalized omnibus cover: 
Except those paperbacks are pretty fragile now, while that Mystery Book Club omnibus is still sturdy.
Another problem with omnibus volumes, even paperback ones, is their weight. The heavier a book gets, the more difficult and awkward it is to read. Put three or four novels between one set of covers, and you get three or four times the bulk. Less if the publisher moves to smaller type, as is often the case, but always more than the individual books. With this extra bulk comes another problem: spine strength. In my experience, any paperback omnibus is going to end up with a creased if not cracked spine by the end of even the most careful reading. Hardcover editions are pretty much exempted from this problem, but then their weight is against them.
I read a certain amount of fantasy, and often – thought not often enough! – these have maps in them. An omnibus may have one map at the beginning or, if it’s hardcover, as the frontispiece. But that’s going to be it. If the individual books had separate maps in them, it’s almost certain the collection will not include them all. Since I like maps and refer to them often while reading such a book, this is a big negative for me.
As mentioned under the good things about an omnibus, the novels may have been reviewed and revised by author. If you don’t like this idea, if you want the original words, warts and all, then this isn’t a good thing. There are a couple of collections of short stories by John D, MacDonald, The Good Old Stuff and More Good Old Stuff in which he “updated” the stories to make them less dated. Let them be dated, I say. I want to read the story as written and published, not updated or massaged into political correctness.
Last, it’s disconcerting to me to have finished reading a novel and still have a bookmark sticking out of the middle (or wherever) of the book. Somehow, finishing the book, closing it and putting away the bookmark (or tossing away the slip of paper or whatever has been used) is part of the process of finishing a book. To have that bookmark still there bothers me a little. Sure, I could take it out, but then would I remember which novel was next in my reading? Which brings to the last of the down side things. I can’t always, or don’t always want to, read the whole thing at a gulp. Sometimes I want to read one of the novels now, and another one in a couple of months. So what happens? Does the book stay out in a ready-to-be-read area of some kind, or go back on the shelf with a bookmark in it, or?
Good, side, bad side. Up side, down side. To omnibus, or not to omnibus?