I made a serged quilt top once. The extra thread in the seams made the seams bulkier, which in turn made it more difficult for me to match seams exactly when piecing. The extra thread in the seams also made the seams stiffer. I ended up going back to my sewing machine, as I can get much more precision with it.
I would use a serger on denim, with red stretchy thread, to make decorative exposed seams. Serging might work well for patterns that don't require matching a lot of seams too.