I think Prez was directing that comment at me, and No, I didn't. I haven't run into any problems, and the beauty of buying good amps, is that you can wait for it to overheat a few times and use that as an indicator of the need to add a fan.
I had that happen in my 5er, and once I added a couple of small fans, they never shut down again. I wish I would have taken pics of that install, it was bad ass.
epistemology: It's not really rocket science, or in your case knowledge science-LOL. Any of those configs would work. Really a fan is an afterthought, it just has to be well placed and functional. Design a great amp rack for your particular application, and use those skematics as a guideline on how to utilize proper fan placement.