The 617 makes a great understudy for the 681/686. For steel challenge I never REALLY needed more than 6 shots. If I did, you lost the round anyway. For bowling pin the 10 might come in more handy, but again, if you needed them ALL, you lost. I like the 10 shot with an Ansac (or other type) speed loader. I haven't sold the Ruger MKll target bottom feeder yet though.