I agree that there are a dearth of professional reviews of this amp, so you are forced to dip into the muddy waters of gear forums. I offer this: I chose a new 502p in 2012 because the factory upgrades were cheap (not sure if it needed that, but it made me feel better), it's the only tube amp anywhere near its price to have XLR inputs, the model had recently been improved/updated, it has 8 and 4 ohm speaker outs, it seems to be well regarded by all but the most snooty among the audio comunity, the Jolida MD dudes (including the company owner, Mikey) are accessable on the phone for a litany of stupid questions, and NOBODY makes a tube amp this good anywhere near its price, even with the factory upgrades. The thing is powerful (note that if it's NOT powerful enough, you can buy 2 and run each in mono for about twice the power...and still they cost about half of anything comparable), quiet, looks cool, and sounds glorious.