Marv, thanks a lot for the review. I was doing a lot of curved cuts on walnut, and tried a template with a straight router bit. I got bad tearout, and eventually used an oscillating spindle sander instead. I wondered about the differences between a straight bit, skew bit, and the magical compression bit, but, at that time, with all of the variables and unknowns, I went with the sander.
I looked at what some of the guitar builders were doing, since they make a lot of curved cuts. I might look into one of those bits if I need to do more of that kind of work.
For me, the straight bit on MDF worked perfectly, but when I did the same template/cut on solid walnut, the result was regular tearout.