Here is a link to the Garritan GPO VST Plug-in which features a direct comparison between a Real Orchestra and the GPO Sample set.
See what you think.
BTW If you wish to use the Garritan VST with an Open Arranger Keyboard, you will need to assign the volume control code to the modulation wheel code, as Garritan use the modulation wheel to control volume and expression

English Riviera:
Live entertainment, Real Ale, Great Scenery, Great Beaches, why would anyone want to live anywhere else (I�m definitely staying put).