I have found that for xmrig and luk-miner that Ubuntu server 7.10 is a little faster than 17.04 which is a little faster than 16.04.
17.10 server seems to be about 10 H/s faster than 16.04 on my open compute servers, so thats what I use.
For my desktop that I have my wallets on I find that 16.04 works the best because some wallets use older versions of dependencies than 17.04 or newer have, and its just easier to run 16.04 than to try to make a wallet work in a newer version of Ubuntu.