The MSI X99S SLI PLUS motherboard played well with both Ubuntu 14.10 and Fedora 21 that are powered by the modern Linux 3.16 kernel. As a quick comparison just for kicks I ran some benchmarks using all of the same hardware and the stock settings for each of F21 and Ubuntu Utopic on this system with the latest packages as of yesterday~today.
You can find these benchmark results via 1410025-LI-FEDORAUBU02 on OpenBenchmarking.org.
It's worth noting though that Fedora 21 during development stages enable a lot more debug options than Ubuntu Linux, which can lead to lower performance... However, overall Fedora 21 still had a nice showing and competed against the Utopic Unicorn. As each distribution is closer to its respective release will be plenty more benchmarks with a diverse selection of hardware on Phoronix. If you wish to run your own Linux distribution performance benchmarks you can easily do so with the open-source Phoronix Test Suite automated benchmarking system.