Although this setup might work, there is a lot of empty space which does add to the image-memory..
Dividing this sprite into three might allready take the amount of image memory needed down a lot..
Also this sprite seems to have several re-usable elements if the layouts are going to be bigger than this, which if seperated could again reduce the amount of image memory needed..
So I guess it all depends on your needs and your further "visual" plans..