Haha, you've been reading another thread haven't you.... The P4 has considerably more power (enough for HE-4's) the 2Stepdance does not. The P4 is a lot of fun for people like me who like to tweak and customise a signature to suit other gear. The 2Stepdance uses 5 x OpAmps (OPA209) and a circuit optimised for them. I'm not sitting oon the fence here but they are both great amps with strengths (and weakness) in different areas. The 2Stepdance makes my ES5's sound better than my P4 but lacks some authority with hard to drive full sized phones whereas my P4 is still great with my IEM's on low gain but in high gain it has the grunt to power almost anything well. The only thing I would consider trading my P4 with is the other high powered iBasso PB2 (32v voltage swing). So they are both keepers but for different reasons.