Quote - As I've never used it, I won't assume it's the same, so what does Poser's "perspective UVs" do? I'm told it hoists a photo onto a prop at a given starting orientation, as you've shown here. But I won't assume that's the case. Plus there may be subtle but important distinctions that lead to failure.

It does the same thing but it's fairly limited in practice. Ideally it should be a projection choice in the image node with an input for a camera name. That way it would be easy to tweak and you could setup multiple projections. The way it is now is mainly useful for simple scenes, but in simple scenes you may as well just model and texture everything rather then bothering with cam projections.

To further elaborate with an example, if you look at the pix above, note that i'm only moving the camera so that the same 3 sides of the box are visible at all times. This is because the other 3 sides are a total mess :) To do a camera move in which all 6 sides may need to be seen, you would need 2 separate projections on each of the 3 sides and then blend between 2 different photos using them. For a more complex object, you may even need a whole lot more. But this sort of thing is not easily doable with the tool poser currently has.

Quote - blender can do this better and its free.

True enough. Blender punches way above what it's lightweight price would suggest. Some of it's features, like fluids, even put high end apps costing thousands of $$ to shame.