Depending on the quality of your main speakers and their ability to image, a phantom center can be a better alternative to an actual speaker. Although the dialog won't be as "anchored" for those on the sides, integrating a center channel speaker (for music) can be quite challenging (much like integrating subwoofers).
I used to have an actual center channel. I currently use a phantom center and find that the image is much more cohesive this way.
I used to have an actual center channel. I currently use a phantom center and find that the image is much more cohesive this way.