>I've encountered this ending a few times and I don't find it too hard. I may not do it the quickest or most efficient way, but I can get the job done. I also insist that the young kids, whom I teach, learn this ending. It takes them a while, but eventually they understand it.
>I've never seen the K + B + N vs. K ending arise in 40 years of playing chess. From time to time, I review it because it's a good exercise. It's not easy and if you're not careful, the 50-move draw rule can kick in. However, if you know what you're doing, you should be able to do it in less than 40 moves from any conceivable position.