Just in case you do decide to look at regular double strollers, let me recommend here.
We have a jogger and a fold-up stroller, both side-by-side. I've -- conservatively -- walked 1,000 miles with the jogger, but have NEVER used it for jogging. We have it because, unless the sidewalks are perfect and you're not walking very fast, the fold-up isn't very good for getting around outdoors. The jogger, however, can take a real beating.