I've looked at all the free ones - JCE is the best open source Joomla Editor out there.

However, that doesn't mean it is an effective, bug-free editor.

Pros:
* The flash tutorials are great, but very basic.
* Great plug-ins, and lots of control over button layout, and who gets to see them.
* The advanced (member-only, payment required) plug-ins are really nice.
* New Show/Hide HTML link is quick and handy/

Needs Improving:
* Install is fragmented. Follow the note above. (the nice 1.0.4 Flash tutorial has the install order wrong, so it won't help 1.1.0 users)

Cons:
* Documentation is pitiful.
* Current 1.1.0 version is beta, so don't expect stability.
* This version breaks compatibility with older plug-ins. This really hurts the product, because you are forced to give up useful plug-ins when you upgrade.

TinyMCE -- The Biggest Drawback:
TinyMCE wound up wasting LOTS of time for us in our last two Joomla projects.
* It doesn't predictably handle structured content based on divs and spans.
* It doesn't handle embedded flash or forms.
* It inconsistently applies named styles from your CSS: maybe you get the tag you wanted, or you might get spans or divs. No rhyme or reason.
* In general, TinyMCE likes to clutter up it's HTML, even with the Clean HTML option set.

Conclusion:
If the author of JCE can document the project adequately, and get rid of the bugs, he will have half of a great product. Sadly, all that greatness will still be neutralized by the inadequacies of the TinyMCE editor.
Still, JCE is the best WYSIWYG editor that the Joomla community has.

-Ken

Pros:
* Decent editor.
* Installed cleanly.
* Seems to do a good job of keeping your markup intact.

Cons:
* Doesn't render multi-column float-based layout -- at all.
* Can't specify styles for markup.
* Loses undo/redo history after going into HTML view -- even if you make no changes.
* Bug trying to modify/insert image (as of 5 Dec 2006).

Summary:
* If you have basic needs and simple layout, this plug-in will do.
* There are better free choices.
* You have to wonder why the company provides it, as it is not a good sales tool to entice people to buy their flagship product.

Claims to be GNU GPL, but only the Plug-in is. The actual editor is closed-source, but free.

Installation is not hard, but the product is split into two parts. You have to dig up the readme file to find out where to get the editor. Since a third of the reviewers did not even succeed in doing that, you can't say this is a good approach.

Now to the editor. Unfortunately, the problems dominate:
* Strips out valid header and paragraph tags from existing content.
* Doesn't have a clue about how to render multi-column layout.
* For whatever reason, doesn't access your template, so styles presented don't match styles in your style sheet.
* Insists on littering your HTML with an obnoxious 'Generated by' comment.
* Can't even specify common tags, like h1, p, etc.

One plus:
* The Screen Reader Preview is a nice option

Conclusion:
If this commercial company is hoping to generate sales for their 'Pro' product with this free offering, they will be disappointed. It is too few features, and screws with your markup too much, to compete with the better completely free offerings here.

Pros -- Powerful, versatile. Some very good code in places.

Cons -- Terse documentation leaves out critical details. Module setup screen is huge and confusing. Inconsistent implementation of menu functionality across the various menu types. dTree menu setup is 'magic': arcane, badly documented, easy to screw up and hard to understand.

Summary -- Extended Menu generates many questions and few answers on the Joomla forums.
* If you are a beginner, and one of the examples is exactly what you want, you have a fair chance of success, unless it is the dTree menu.
* If you are an advanced developer, the cost of modifying the module to get exactly what you want is almost equal to the cost of building it yourself from scratch.
If you are one of the few who can make it work, more power to you. The many who can't should look elsewhere.