55 hours on my DX90, far too few of them involving me, about 53 of them have been looping the burn-in album through the burn-in album to clock some hours.
Those Sabre DACs are awesome. They really give you E V E R Y T H I N G. All the tiny details, all the spatial clues. This means that live albums only sound "large" if they're in a large venue. Example: Muse - Live At Rome's Olympic Stadium clearly sounds larger than Adele - Live At Royal Albert Hall. Black Background? PITCH BLACK - if the recording is dead quiet. This is bad news for bad recordings and revealing headphones, but feed it quality material and the DX90 delivers. Everything sounds so very real - we're in DX100 territory here, but at half the price and half the size.