I've thought about headers a few times for mine. I think the cheapest ones are about a grand for shorties. It only takes about 90 minutes per side to do the manifolds now, and the bolts are free with the lifetime warranty, so I pick a weekend and spend the 3 hours swapping out both sides once a year when they break.
I put a new set of manifolds on last time, it's been 12 months and about 10k miles, so far so good.