I used a neutral blue background I purchased from my LFS that was cut to measure of the 10 gallon it sits behind.
It came with one side neutral blue, the other neutral black. I chose it out of sake for aesthetics; I didn't enjoy looking through the aquarium to the wall behind it. Eventually, I am going to switch it to the black side, but because I am not doing much with my 10 gallon aquarium right now, it is a back burner project.
I've never used a background that has a fake extended aquascape picture to it. It always seemed like a strange idea to me.
BUT -- With my experience noted with my blue background, if I could find a brilliant aquascape that matched my color scheme in my 10 gallon, I would more than likely choose it instead of the neutral black or blue. The backgrounds are designed to provide you with additional depth, and some of those with great color schemes I could see benefitting a smaller aquarium with less bearing to it than a larger 100 or more gallon tank.