ah ok. I have found that unplated copper plugs do not have as much resolution as even the gold-palted. Unplated copper is very punchy in the midrange, but it lacks high frequency detail and I feel that it smears the sound just a tiny bit.
The gold-plated Neotech will likely be an improvement in resolution and tonal balance. The Furutech rhodium will have the most detail, tight deep bass and extended high frequency range. If your cable is not extremely thick, the lower price Furutech FI-15 Plus (R) rhodium connectors are an excellent value at about $55. You just have to be careful not to tear off the casing when you tighten down on the clamp screws. The casing folds open and it attached at 2 points with flexible plastic.