I received the Geckos about two weeks ago and have had them on my speakers (Focus Audio FS888) since then. Compared to the Cardas copper jumpers they are replacing, I am very happy with the results. I am using them in combination with Acoustic Zen Hologram II single-wire speaker cables. Relative to the Cardas, the Geckos seem to offer better speed and openness without impacting the tonal balance. Relatively speaking, the Cardas jumpers made vocals sound a tad closed in with a little bit of harshness.
FWIW, I've reached this point of getting high quality jumpers after becoming somewhat disillusioned with bi-wiring. Prior to going to jumpers, I had used a couple of different configurations on bi-wiring...Audience Au24 high and low, Audience high Acoustic Zen low, AZ high and low...and while each configuration did result in something positive, each also seemed to lose something in the overall balance or naturalness. Of all the bi-wiring configurations, I liked the AZ high/low the best...and maybe there is something to the design (AZ seems to prefer bi-wire designs, whereas Audience doesn't believe in bi-wiring)...but I feel I'm getting the most natural results using single-wire and these Gecko jumpers.