What PC do you use...

Of course PC performance is system dependent. Just went through extensive trials (8 cords)over 4 months with the Premier. The best cord was the inexpensive VH Audio Flavor 4 (Furutech connectors). Some well regarded cords that were significantly more expensive were part of the trials.

Cerious Technologies with my Cullen modified P500. Bested everything else by a substantial margin including Electraglide Ultra Khan II and PS Audio Plus.

Fusion Enchanter on my PS300!

Stew

Can you describe the sound before and after the mod?

Tabl10s:
Honestly, its about 11 months since I had the mod done, so I can't recall specifically what the mod did sonically, except to say I was extremely happy with the decision to upgrade at the time. In addition to better sound, the mod added a remote and made the unit run more efficiently. The fan runs at a slower rate so it is a bit quieter. I can also tell you that when I spoke to Barrows at PS Audio he told me that the modded P500 was competitive with the newer Premier. Since I use the P500 for a speed contoler for my VPI Aries II with the dual motor flywheel, it also takes the place of an SDS. I personally thought the upgrade a wothwhile investment.