The Word editor comes with a relatively powerful set of editing tools that are certainly a step above those of the Google Drive app. It lets you change font sizes and styles, paragraph settings, spacing, and more. It also lets you insert images or custom tables into your documents.
Meanwhile, the Excel editor is just as robust, as it comes with formatting tools and a handful of options for adding, deleting, and otherwise manipulating rows and columns. One of the coolest parts of the editor is the formula module, which makes it easy to enter commonly used statistical, arithmetic, and trigonometric functions into your spreadsheet.
One thing that sets Quickoffice apart from Google Drive, is its ability to create and edit PowerPoint presentations. It comes with all of your basic formatting tools, as well as a menu to add images, text boxes, and shapes to your slides. The app doesn't offer power features for things like animations, but it does have most of the basic tools you'll need if you're editing a presentation while on the go.
As powerful as Quickoffice's editors are, they did show some weaknesses when it came to rendering some elements in files. For instance, with Word files, Quickoffice failed to render text-wrapping formatting around my images. Meanwhile, a competitor, Kingsoft Office, did just fine with the same file. Also, Quickoffice didn't support a few select charts in my Excel files and PowerPoint files, which was disappointing.
Quickoffice is great because of its dead-simple file manager and robust editors. It can handle Word, Excel, and PowerPoint files natively (so you don't have to convert anything), and it can connect directly to your Google Drive account for easy backup.
Even with these strengths, however, this simple, yet powerful app still has room to grow. First, it needs to be able to better handle elements like text-wrapping and charts (it renders some charts well, but not all). Second, it would be great if it could actually edit Google Docs files natively. And finally, while Quickoffice's interface is certainly simple and intuitive, it's still not as visual or as effectively organized as it could be. For instance, Quickoffice's nested menus work, but they're not as easy to use as Kingsoft's scrolling, icon-based toolbars.
Overall, Quickoffice is a solid Office editor, but it's still not the best. If you're looking for a way to edit Excel, Word, and PowerPoint files while on the go, then pass on Google's product, and go for the more powerful, and also free Kingsoft Office.