Whether Win4Lin can completely replace a native Windows installation remains to be seen. For low-intensity exercises like Microsoft Office interaction it does pretty well, but propagation delays owing to operating Windows within Linux may be problematic for professional graphics designers. Image editing and manipulation programs like Adobe Photoshop or Jasc Paintshop are resource-intensive and can fully exercise underlying hardware resources even for moderate tasks. That said, either dual-boot configurations or substantial hardware investment will produce the best results for such applications.
Any application built upon the DirectX graphics library won't work under Win4Lin owing to its lack of built-in support. Everything from modern game software to Internet Explorer programs utilize DirectX to render a variety of graphical effects, some of which are then used in benchmarking applications that would otherwise be useful for comparative analysis.
This does not mean Win4Lin is unsuitable for ordinary usage requirements, however. But considering that gaming functionality differs vastly from the majority of desktop applications, which explains the specialized capability of TransGaming's Cedega framework, Win4Lin does a fine job of meeting its target objective. Ostensibly, this is to enable Windows applications to operate while Linux is live, and Win4Lin delivers exactly that for many productivity and content creation suites.