Threshold in my opinion blows away Aragon by a far margin. All Threshold is solid state. The S150 is a class A/B amplfier producing 90 Watts RMS at 8 ohms per channel. It has 8 high speed 200 volt,20 amp rated devices per channel.Power supply is a 400 watt toroidal transformer,30,000 microFarads capacitace.Frequency response is -3db;7Hz an 100,000Hz. Gain factor +26.6 db.Operation is allowed into any load as permtted by power supply fuses and thermal protection. All Threshold Amps were required to pass a dead short test,both before and after the initial 3 day factory burn in into a 2 ohm load. Needless to say all Threshold products must pass the most severe test,before they wear the Threshold label.