Unreal Engine 3 with maximum quality

The Unreal Engine 3 is quite a popular piece of software. But what is the maximum quality you can get out of it? PCGH checked it out in Bioshock and UT3. The shots were made with an GTX 260 and a 8800 GT (G92). Resolution: 1,680 x 1.050 (16:1 AF) with diverse settings.