it does what is says on the tin - and it does it great

The image correction, even in complex compositions, is very impressive. This is the case even with lenses which distort architectural images quite a bit (e.g. Nikkor 18 - 55mm) and not evenly across the frame. The software is super fast as well.
The only downside - the software is not an extension. I wonder why, but it really should be!

Wanni about DxO Perspective