Hexcrawl Review: Dungeon Master's Guide

I want to do a couple quick reviews of terrain generators and hexcrawl stocking methods  that I've seen. Not a thorough review, but more of a quick assessment of procedures that may help or hinder generating the world during the game (as an improv hexcrawl) instead of during prep. I'll try to do a standard five-hex diameter test map for each, for comparison.

First up: Appendix B in the AD&D 1e Dungeon Master's Guide. This is a very simple, two table, one page system for generating terrain in unmapped areas. The main table gives chances for each terrain type based on the terrain in the current hex. The companion table determines whether it is inhabited or not.and is heavily weighted towards uninhabited wilderness. It's one of the few terrain generators that seem to be geared towards using during play.

Pros: Simple and quick. Terrain is somewhat logical (no marsh next to mountains, hills and forest can intermingle.)

Cons: Some extreme elevation differences are still possible. Only handles the broadest detail. Speed will depend on the number of hexes needed.