The HPA 2 and 3 were basically Levinson models. I spoke with a dealer some years ago as they were selling the 5 channel. He said those were superb sounding amps and it was really a shame they discontinued the Proceed line as it gave people a taste of the Levinson sound. Those and are heavy like tanks. The only thing you need to be aware of is service and age. You cannot service those amps at Harman. There is a place in Mass (forget the name) that is recommende to service the Proceed amps. I think it's near Dedham, Ma. And in terms of age, all those amps will be at least 10 years old at this point. I think the Proceed line was stopped sometime around 2003 or so.