For many years I took great pride in my skill drilling large holes using twist drills. (Up to 2" diameter in steel up to 3 inches thick.) I have over a dozen air and electric drills and a large drill press so holes have been something of a specialty for me.
This is my first experience using annular drill bits and I am kicking myself for ignoring them for the past 40 years. (One should not allow price to cause lost productivity.)
The holes are so cleanly cut they look like they could have been produced on a milling machine. Unlike twist drills which tend to wander a bit under even the best of conditions these bits stay true and produce a nice close tolerance hole and in minimum time.
I build specialized truck bodies and the holes that once took me all day to produce are now completed in an hour or so.
I needed to produce a number of small reinforcement plates with 5/8" holes the other day. In the past it would have been pilot hole, larger hole, then larger hole until the holes were all the correct size. With the annular bits it is a one time shot from zero to the correct size. It took me longer to lay out and center punch where the holes went than it did to drill them.
Next on my list is to start adding more bits in larger sizes.