Rowland Synergy IIi, but it doesn't have a phono stage. With companion Rowland Cadence phono stage, it would cost roughly $4,000-$4,500 used. Other than the darTZeel and Rowland's Coherence II (my preamp), it is the only consumer preamp I am aware of with a 50 Ohm output impedance. In fact, it was built to be used with Rowland's Model 2/6/8/9 amps, which all have 600 Ohm input impedences.
The Rowland is very well built and I would not worry about buying used, especially because it is powered up constantly (no on/off switch) and thus can't be abused by the owner turning it off and on.
The Rowland is very well built and I would not worry about buying used, especially because it is powered up constantly (no on/off switch) and thus can't be abused by the owner turning it off and on.