Anyone try the "hybrid" copper/silver ic's?

I was thinking of picking up a set of Kimber Select 1121 ic's. These are hybrid's. My Amp is the Rowland concerto. Using my Behringer 2496 as a dac. Thanks.
I've tried the Xtreme X-2 hybrid ICs. I ran them from my preamp to amp. I believe the ratio of copper to silver is in favor of copper by a pretty good margin. The ICs sounded nice, no excessive brightness and very smooth.