I'm looking to eek out just a little more power on my 16v, i have the cat back exhaust from calmini, i have an intake.  So really the only thing missing is the headers.  Will they make enough of a difference to justify spending the $200 or so they cost?  Or should i save it and apply that money to more off road parts? (i.e. suspension, rims, tires)

I'm not a professional but from what I've been told the factory 16v manifolds flow pretty good and the cost is not worth the gain. But like I said I've only been told that not experienced it.

I know the Stock Exhaust Manifold is known for Cracking around the #3 Cylinder.

Sometimes you still can't hear it, but I assure you it is VERY Common.

The Header would be an Effective Replacement over trying to find a Stock Exhaust Manifold. 

I know the Stock Exhaust Manifold is known for Cracking around the #3 Cylinder.

Sometimes you still can't hear it, but I assure you it is VERY Common.

The Header would be an Effective Replacement over trying to find a Stock Exhaust Manifold. 

Yes VERY common. Mine is and the other 6 I have seen are also crackes in the exact same spot. Poor casting design on Suzuki's part.

From what I understand the 96+ 16v manifold was redesigned, & it is a tuned manifold. If it aint broke, don't fix it... Cracked? Well it's broke, fix it ofc...weld, muffler mender, replace, or pricey header that's prolly not tuned. m2c

I had one on mu 1.3 and it did help on the upper end but on a small offroad vehicle it looses the low end power due to lack of back pressure. I sold it and reinstalled teh stock and it still runs just about the same as with the header. I wouldn't bother if I were you.

I love my Doug Thorley Header and yes it was worth it.

Will they make enough of a difference to justify spending the $200 or so they cost?  Or should i save it and apply that money to more off road parts? (i.e. suspension, rims, tires)

The problem is "worth it" is interpretable. People who are happiest with their header purchase tend to be the one's who've already done the other intake / exhaust upgrades (they're probably the most restrictive parts). No matter what (like your exhaust and intake), you're only talking about a few HP / Torque gain. You'll just have to ask yourself if you're more interested in engine performance, or suspension / tire performance.

This may be useful: http://bbs.zuwharrie.com/content/topic,82730.0.html