This is a great post, except after 2 years of exclusive DB pressing, I'm just as strong on DB's as BB's. Which means my BB bench blows.
Keep a natural arch in your back.
As you get stronger, the DB's become much easier to control. It takes time. It took me forever to be able to lean back with the 105's when I first hit them without almost dumping the weight. Now I can lay back with the 125's pretty much under control/feel strong and read to press.
The first rep is always a bitch with the DB's. Get a spot to help get the first on in the air if you have a training partner, you will get 2 extra reps out of each set, if not more.