Judy Niemeyer makes such gorgeous patterns! I have two of her PP patterns and after reading the instructions, they seem to be explained very well. They are almost a course in and of themselves. One difference I can see is that she also includes patterns/directions to precut the fabric pieces before paper pieicing so you don't waste as much fabric.
Since you already do foundation paper piecing, is there is something more to your trip, such as seeing the area, visiting a relative or friend, then it might make the substantial cost more worthwhile? Otherwise, it sounds like budget should be your determining factor.