I'm developing a complex newspaper style theme for WordPress. I want this theme to be customizable by many users (e.g. if I made it available to download).

I'm torn as to whether or not I should go with a grid-based structure for this theme. Would that make it easier for end-users to change column widths, etc? By grid-based structure I mean something like grid960, Blueprint or this: http://www.webnicer.com/

Do grids work well on other platforms (e.g. mobile phones)? Are they considered among the best practices? If you've used grids before in a client project, how easy have they been to maintain if the client wanted to make changes later on?

Or would it be better to avoid the grids altogether?

I need your opinions, thanks!