IPS panel vs VA panel

If you're asking for the panel itself, not referring to a specific model, the advantages are follows:
Wider viewing angles
Better color accuracy
Improved black levels

Disadvantage:
Panel has slower response time

I will absolutely say, a cheap IPS monitor can easily get trounced by a quality TN, or VA panel in many ways. While IPS looks light years ahead of TN or VA on paper, you have to take into account the whole package before blanket stating IPS is far superior.
 
IPS screens have a slower response time than TN and VA panels. That's the reason they are not generally the first choice of gamers, and until this year's Panasonic LCD line, used in television sets. I have no idea what screen stability means.