Pix, I liked my 5400, it drove a pair of Dynaudio Audience 60's without a flench. It has a slight mid bass hump which is fun for Rock and Pop. The down side is it can be a bit bright. If you can go the money it's worth the difference for the 5500 though. More power, better bass with more control and the mids/highs are improved. Both amps will require good ventilation although the 5400 could live with less than the 5500. For the price of the 5400, and especially now used they are a steal.