Buy the Pass X600 amps for these reasons: 1. All things being equal, more power is better. Greater soundstage. 600 WPC. 2. New technology. 3. Much less expensive in comparison to ARC, Levinson, and Krell. 4. Rave reviews. Never a negative word said. 5. Pass has always done something magical when it comes to amplifiers. Good Luck - I am buying the X600s
