Your right about saving time, but every once in a while within a scene, something that doesn't show up while your putting a sceen together,something will happen, and you have to rerender, example. one of my  sceens the render started changing the lighting, and went black, then went back to the normal Lighting. The bad news is, I had to      re-render. The good news. I only had to render the frames that started going bad. I get a more consistant hi quality of the renders with images, and any adjustments that I might have missed, usually are easy to correct. One other thing I can do easley is pull out an image that can be a promo image sometimes yeal easely.

The Adobe images, I do have always done the things you have mentioned, but for some reason when I set my original 1 frame per image, it always comes out 2 frames per image. Not such a big problem because, I am rendering image files for the next movie sequence clips in the background. but it sure would be nice if when you set the sequence to go down to 1 frame per image. It would take a hint that I want 1 frame instead of 2 each image as I spefified. Thanks though, if I wouldn't had been doing my images already as you mentioned, that would be good information for anyone else to know.