As for both as someone who has machined in shops for years, and also taught for years i can say from my experience centerdrills are used almost exclusively. The reasons for this is accuracy and cost. The design of the tool keeps it very rigid thus making it very accurate, usually we find play in the machine causing holes to be off before we find the center drill walking. The next is cost, a center drill is used for all materials, for all different machines. They are cheap, they all act the same and you don't have to waste time deciding which angle you need to use. We run them in everything from 15-5PH to 6061t6 and always have predictable results. As for common drill angle, the vast majority of jobber drills are sold are at 118 degrees again this is the same as the center drills it is cost and predictability. Time spent checking angles for proper material in accordance with the cost of having a whole bunch of extra drills sounds counterproductive and more expensive to me.