Quote - Everywhere I have read, says that burning slower can avoid problems, and burning over the rated speed (ie burning a 4x at 16x) makes the problems.

I don't recommend burning over the rated speed either.  In fact, I didn't think one could burn at a higher speed than the disc's rating (maybe one could set the burning app to a higher speed, but that doesn't mean it's actually exceeding the disc's rated max).

Quote - One other thing... on any CD or DVD burn, at least as far as I have ever heard of, the app creates an "image" of what's being burned to disc... it creates a file of the file(s) that are going to be burned to disc in the format that it will be, on the disc, then uses that to do the actual burn.

That may very well be true - it sounds likely.  However, in my experience with these suites (admittedly years ago, since I stopped using them), if the process is interrupted and the app crashes, there is no image file to point the app to - that is, the whole process must be started again.  This implies that even if the app is burning an image, the whole process is one big stream and one problem anywhere can bring the whole process crashing down.  I prefer to control each step myself, with non-bloatware (create the iso - did it work? good.  Now I can deal with burning the image do disc, rather than wondering where the problem occurred).

Then there's the (IME) wholly problematic method of burning (name escapes me) where the app treats the burn like a regular Windows file system - you can add files at will and the app burns them one at a time.  Never had anything but trouble with that shyte.