Quote Originally Posted by daq7
I believe that more shots probably averages out random noise better, but I cannot prove it. Most of my HDR work now involves taking ONE raw shot and manually blending exposure layers from it. I still often use a photomatix layer as one of the blended layers, but I haven't been doing a lot of shots with HDR software. I agree that for the vast majority of shots -2,-, and +2 are good enough.
+/-2 is a bigger step, and Adobe does recommend using 1 step increments to keep the image smooth. I think Photomatix is vastly superior though for HDR merging, and Topaz can do quite a job with a single exposure.

In my experience, and I do post a fair amount of HDR photos here, +/-2 works very well with photomatix. Most of the latest landscapes I've posted here are all HDR tonemapped photographs. I've been off my game lately because of a big move, but once this all settles down I hope to get out more again.