In a word, well. The audio output has little bass response and sounds a little "thin" compared to the high fidelity output of a Super_Pro, but still better than many solid-state receivers. You'll need to use audio transformers to match the receiver's 600 ohm output to today's low impedance speakers (high efficiency only, please!) and audio distribution systems. Even then the audio won't be overpowering. The frequency stability is excellent after a reasonable warm up period -- constant "touch-up" tuning is not required even over long periods of listening. Frequency readout is quite good *after* calibration with the built-in calibrator somewhere within a couple of hundred KHz of the desired frequency. Dial markings (with a reasonable space between them) are provided every 5 KHz on the 2-4 and 4-8 MHz bands, and every 10 KHz on the 8-16, 16-24, and 24-32 MHz bands. It's really not a problem finding a particular frequency -- the projection dial will get you within a couple of KHz after you've done an in-band calibration. The repeatability of the 0-1000 dual-rate logging dial is incredible (this is not affected by in-band cals). Stations can be found within +/- half a "mil" in most cases. The tuning rates and ranges make band "scanning" convenient, ie. R390 wrist syndrome is *not* a problem.
The broad IF filter is good for shortwave broadcast listening under most conditions, but heterodynes are a problem under crowded band conditions. Using the A3 sharp position (mechanical filter) provides relief at the expense of fidelity. Operation on CW is excellent in the A1 broad, medium and sharp positions. SSB reception is reasonable using the RTTY position, which provides some AGC and uses the mechanical filter, but not up to the standards of receivers designed for SSB service.
The SRR-series receivers do not enjoy the outstanding reputation and "net press" of earlier RCA Navy receivers like the RAL, RBA/RBB/RBC, and the legendary AR-88's. There are good reasons; they are difficult to work on, don't have hi-fi audio, and use "weird" tubes. In spite of this bad rap, the SRR's can be very good performers.