I have had the PSX 5.3 now for almost a month. I was so impressed with the sound of the phono stage that i ordered the power supply from my local dealer before it was ready to be shipped.
The PSX 5.3 takes at least 300 hrs to sound its best , at 200 hrs the break in was about 80 % complete. The largest improvement is in the top end and innermost details. This power supply allows you to hear differences in cymbals and bells like you have never heard before. Fine inner details on multiple horns and stringed instruments can be heard clearly and each individual instrument can be heard .I found a slight loss of bass impact but a huge increase in the detail of the bass especially in the cello and stand up bass. The echos are also more extended and more of the recording room can be heard. I think all of the improvements can be attributed to the extreme quietness of the phono /power supply combo. I would highly recommend the power supply.
If you purchase one follow the instructions supplied , you must remove the top of the phono stage and change 2 jumpers to prepare the unit for the external power supply or you could damage the phono stage since you will be trying to power the unit with 2 power supplies, the internal and external.
Todd