OR
I've always had trouble with the distortion that occured when flat mapping an image to a curved surface.
Cylindrical mapping is best especially with wide format images, which wrap around the circumference of the curved surface.
With flat mapping you can simply use the scale tool to resize an image. Not so with cylindrical mapping. Setting values for the tile size and offset are trickier, but they work better to avoid distortion. These Xpresso group automates most of the process (there's also a spherical version).
Open to all criticism. Instructions as to how to use my method are included on the file within the Xpresso tag.
Hope you like it!
Kevin