If your (Mac-only) word-processing needs fit within Writer Express’s feature list, the generally sensible UI will make it a superior alternative to Word. Within its limitations, it’s an excellent, useable program.
However, if you need table support that’s better than an ancient version of Netscape, real Word interoperability, or precision layout tools, look elsewhere. For now, at least; they’re working hard to improve the product.
Note to people with fond memories of the Mac OS Classic Nisus Writer: Express implements a subset of the old features, along with a bunch of new ones.