>> JAB Creations
In regards to what you say about rendering engines, while in theory what you say is true, I've found that when it comes to actual web designing Chrome and Safari are not always identical. It's never anything major, but I had issues one time with how Safari was treating a form design I was working on while it looked fine in Chrome. Safari was adding extra space to the elements.
YMMV, but that's been my experience and it honestly can't hurt to try both of them.