Calvin and Hobbes. Need I say more? The Sunday strips are conceivably the best (especially since Watterson was allowed his new layout) because there's more space and room for more involved dialogue and/or action. And therefore, a better laugh.
It's also humorous, though, to see Watterson being slammed for doing something that would be unthinkable to him; slapping some strips out into the market for extra money. He hasn't had much control over how many collections and treasuries have been published, so slam the syndicate, not him.
This book is, of course, superfluous for the man (or woman, of course) who has every other C&H book. But for a newcomer, I can't think of a better book to start with.
JK