I have the VA1912WB, and I have a 20.1" widescreen as well. The VA1912WB is a TN panel. Its fine for normal desktop use and a decent gaming LCD, but it is not very good for watching movies, and doesn't scale too well to non-native resolutions. It is also a 6-bit display (although the colors still look very good). The main thing it has going for it is price - its amazingly inexpensive (at least in the U.S.). The VX2025WM is larger (obviously) but also will have much better viewing angles and better contrast, since its a SPVA panel. It is an 8-bit display as well. It will scale a lot better than the 19" as well (partially due to it using smaller pixels).
In the U.S., at NewEgg, the prices are $205 for the VA1912, and about $329 for the VX2025...