I have used Moon guides in the past and have found the editorial approach, quality of writing, and level of content to be excellent (the Cuba guide is a particular gem!) The Belize guide is sadly not in this category. It reads more in the tone of a Chamber of Commerce report- everything is great, fascinating, the best, delicious, and comfortable. Anyone who has travelled anywhere outside of a luxury resort knows that simply isn't true, and it isn't true for Belize either.
The Moon guide also does not appear to be geared toward budget travellers, leaving out important information like how to get to and from the airport while avoiding the $25 tourist charge. The shortchanging of budget information is a particular problem in a country that is substantially more expensive than its neighbor Guatemala.
The guide also leaves out the city of Flores, Guatemala, but includes Tikal. Getting to and from Tikal (except on an expensive guided tour) almost always involves travel through Flores, and competing guides (like Rough Guide) include it, making them more useful than this guide.
The guide has a lot of detail- but if you are a budget traveler, you won't be able to afford much of it. This guide is really geared more to the well-heeled tourist who is driving around Belize either in a rental car or on a guided tour. Moon could, and should, do much better.