SmartClient or SmartGWT?

In my case, code maintainability.

We are a Python house. But for client-side code we opt for GWT, initially with GXT, but now with SmartGWT.

We don't like Java, but we don't like JS much more, Order, maintain libraries for several widgets, extends objects to give custom functionality, etc. between doing this in JS or Java, the option was obvious, Java side. We write reusable components here, and now we write very minimal code for client side, only reuse components and use REST to comunicate with ours Python backends.

We know that SmartGWT is more verbose than SmartClient, but, with Netbeans autocompletion (some coleagues here use Eclipse) we have direct access to every method, documented, instead to go to the showcase or google every time that we need to test and try new functionality.

SmartGWT provides you the advantage that you may use powerful editors.

You can debug your own code easily (however it's not very helpful for diving into the smartclient code itself).

You have all the auto completion stuff of eclipse/netbeans at hand. When starting to work with SmartClient/Gwt it helps you find the things you are looking for because the editor can list you classes or the available methods and some basic documentation what the class/method actually does. Saves you a lot of time crawling through the docs

SmartGWT is the GWT wrapper for SmartClient, which, as you say, means that you're able to write your SmartGWT app using java.

From my experience the only difference that matters when you're programming is that the GWT wrapper is a bit more restrictive than using the js components directly. For example, programmatically scrolling a TreeGrid from java is hell, since the body of the underlying table (that you need to get at in order to scroll the blasted thing) is not exposed through SmartGWT, while it of course is easily reachable from js.

Overall I wouldn't base the choice between the js components and the gwt wrapper soley on these differences, but I would look at other factors in your project. Which techniques are you most comfortable with? How much custimization are you planning on doing?