Hi Ron,
Both IeGO and Furutech are "top of the line" brands that synergize extremely well with TWL's audiophile wire.
The IeGO connectors for NEMA (US version) applications utilize Japanese Furukawa copper. Furutech gets their namesake from Furukawa. Furukawa is noted for its high-purity copper, often using an oxygen-free manufacturing process to achieve exceptional purity.
For North American (NEMA) applications, I've found that the "Digital American" series works best with IeGO and that the "Plus" series (7+ & 9+) works best with Furutech.
Cheers,
Pete