In my first season of part time trapping, I have caught more predators than I have called in the past 3 years. If I lived on the properties I have been trapping, I could probably have gotten more by now also. Calling is fun, but trapping has proven to be very productive.
I vote for rubber jaw 2 coil MB-550 also. They require no tuning, and they are built very solid. I would rather have 4 mb550 than 6 duke #3 or #4. Duke have their place, and I have several of them. But the mb550 are superior to many of the popular traps of similar size. You will not be disappointed.