I have made identical ICs with 99.99 % pure copper cryo'd solid core wire, good metal-to-metal contact and Cardas solder with the following RCA plugs:
WBT Midline, WBT solderless, WBT nextgen gold and silver, Eichman gold, Xhadow, Cardas silver/rhodium, Cardas gold, DH Labs top-of-the-line OFC plug (I do not recall the model) Vampire Cx7CB and Vampire 800 CB.
In my system, from most liked to least liked:
Vampire 800CB -very musical, best bass, quiet, smooth, analog-like;
Vampire CX7CB -very musical, quiet, smooth, analog-like;
WBT Nextgen Gold -very musical and transparent; actually sounds about the same as C7XCB, both are low mass conductors.
Xhadow Small- very musical and transparent, slightly emphasized treble/air;
WBT solderless - OK, musical, does not excell in any area except coherence;
Cardas Gold -OK, musical; good for the price;
WBT Midline -OK, fairly musical; restricted bass and treble, too expensive for what if offers;
Cardas Rhodium (slightly steely sound, great bass)
Eichman (weird distortion/grunge in the midrange)
DH Labs (bright-sounding)
Digital ICs (pure Silver):
WBT Nextgen Ag - just wonderful; Numero Uno for digital!
Xhadow Large - very close to WBT Ag and more robust;
WBT Nextgen Gold - Great, loses a little transparency as compared to the above connectors;
Cardas Silver - good sound, but not magical as Nextgen Ag
I have not tried the remaining connectors on digital ICs
On analog, I prefer slightly smooth and "mellow" ICs than super-transparent, hyper-detailed cables.
On digital, I want the cable to pass very low-level detail and soundstaging clues (in adddition to souding even-handed)
Audio Aero Capitole CDP directly into ASR Emmiter II, Electrocompaniet or Hyperion SET tube amps, Hyperion 968 speakers, Tara labs Air 1 Series 2 ICs, VDH Supernova bi-wire speaker cables, Fusion Audio Predator, Impulse and Enchanter power cords.
I hope this helps