Complex sentence: The route chosen was 18 miles shorter than the shortest competitor's, as well as better grades than some, but it was an expensive route, since the Milwaukee received few land grants and had to buy most of the land or acquire smaller railroads.
Split into simpler sentences: The route chosen was to be 18 miles shorter than the shortest competitor's, as well as better grades than some. It was an expensive route, however, since the Milwaukee, receiving few land grants, had to buy most of the land or acquire smaller railroads.