I have upgraded to Burson op-amps in as ASR Emitter II amplifier and a high-end CD player.
This is a very worthwhile upgrade, better than monolithic op-amps in every aspect of the audio checklist. Give them a couple of hundred hours to break-in and have fun!
I have about 15 years experience in tweaking electronics. This is a winner, probably one of the best electronic tweaks.
Warning: pay attention and make a note of the location of pin 1 in order to avoid mishaps. You may need to solder a short ground wire between the op-amp and the component's circuit board. I had to add a ground wire on the ASR Emmiter, though I do not recall the reason anymore.
Enjoy!