Black Sheep Golf Club located 40 miles west of Chicago is a 27 hole layout that has the same design philosophy and feel throughout. I've spent the past two summers working there as a caddie.
The layout was built on rolling farmland and has no houses bordering the property. Each of the three nines have huge, wide fairways. The bunkers have ragged edges and the grass about the bunkers is grown long with lots of snarls. Off the fairways and first cut of rough, the native grasses are grown to waist high. The green complexes are well bunkered and have many subtle slopes. The greens are large and typically viewed as some of the best greens in Chicagoland, simply because Black Sheep gets very little play and the super does a great job. The entire site has a seemless feel and flows very nicely together from the first hole to the last.
On the other hand, Bay Harbor up in Michigan is a good example, I think, of a 27 hole facility that has three totally different nines; Links, Quarry and Preserve. I am not a big fan of golf courses like this, which have polar opposite personalities from one nine to the next. I like to see more common features so that I feel like I am playing one golf course, rather than three.