You should include Payprus Office (http://www.rom-logicware.com/) in the review.
The "Office" name is a bit of a misnomer, as it consists only of a word processor and a database.
This program has been around for a very long time (it originates from the Atari, and there is even still an Atari version). It's constantly updated (currently at v. 12.5 for Windows and Mac). It's not cheap ($99), but very stable with long documents, and it has a small but loyal user base, esp. in its native country of Germany.
Edit (premature posting): It's also portable (USB stick friendly), but no outline mode AFAICT.