My stock manifold has a crack. I plan to install programmer/chip any recommendation on the performance manifolds outthere. Is it worth the extra money or just go back with factory manifold?

 

Since you have to buy one anyways I would say go with a 3 piece exhaust manifold, it helps with expansion and should prevent it from cracking again. Unless you find a good used stock manifold for next to nothing.

 

A buddy here purchased AFE bladerunner manifold from 4Wheelonline with good rebate for his '02 Diesel 5.9L just last weekend and it looks nice. He's not planning for a programmer though but should able to handle it. Check here:
AFE Dodge Diesel Exhaust Manifold

 

I would buy another stock manifold. It can support your HP levels unless you are wanting eye candy or going for un-Godly HP levels.