FunkyKit posted a review on the TeamGroup T-Force XCalibur RGB DDR4-4000 16GB Memory Kit
A quote from the article:
Today, we’ll be taking a quick look at the TeamGroup T-Force XCalibur RGB DDR4-4000 16GB Memory Kit. These “Special Edition” memory kits are XMP 2.0 ready and are rated to run at DDR4-4000 with memory timings of 18-20-20-44 @ 1.35V.TeamGroup T-Force XCalibur RGB DDR4-4000 16GB Memory Kit Review
Although the memory timings seem to be quite high, the increased speed of DDR4-4000 should counter balance any latency. And of course, higher memory speeds means higher overclocking ability.
There is one thing to note. Not all motherboards can support high memory speeds above DDR4-3200. I recommend checking your motherboard manufacturer first for compatibility.