Worth it to put headers on a 318?

On a 318 your looking at a 4 to 8 horsepower increase with the cheap headers over the 360 log manifolds. To me it wouldn't be worth the extra cost and hassle over the manifolds.
I have a 3.58 stroke crankshaft in my 340 block and I had the manifold/ header debate too. I chose to put the 340 manifolds on my car. I'm giving up about 15 to 20 horsepower but to me it's worth it.