WOW! This thread might get interesting really quick! I'll be following it closely.

My $0.02. I have used both Pyro (rollo pyro & Pyrocat) and Rodinal in the past. they are two different animals entirely. I think each has its uses, but neither are the silver bullet they are claimed to be. My personal opinion. Rodinal is great because it is cheap, it lasts forever, produces sharp negatives, and so far is easy to find in stores. On the other hand I think it is way over hyped.