Hi, Craig: You may get a range of opinions in response to your question. To be honest, I have not tried the "615". However, my past experience with the "515" was anything but positive. In the early 1990's, I taught graduate classes on U.S. bases in the Far East, and during the day I sold audio gear, which included the Adcom line. The "515" had a fairly high failure rate, and I thought they were nothing but a glorified power strip. Perhaps the "615" is better made, but my personal suggestion is to get a Monster Power unit --either the HTS2000, or the HTS3500 if you want a model that offers sequential turn-on and turn-off for your components. The HTS2000 can be purchased for $125 from Global Mart (see link below), and the HTS3500 sells for $225-250.
www.global-mart.com
www.global-mart.com