On the other hand, if you think there is a good chance you are going to hit a nail a spade bid is one you don't mind trashing. I am an unhappy camper when I hit a nail with a $40 ship auger.
In real life you can bring a spade bit back from the dead on a grinder in a minute or two. I have some that have been reground so many times they don't even like like a regular spade. I made one over 3' long to drill a sole plate from some allthread once (before I saw a Diversabit). It wasn't pretty but it worked.
I agree they are not very elegant and I like a nice auger but if it isn't virgin wood I will probably be using a spade.
