I am kind of glad that he is trying to learn something. Don't take me wrong I would be happy to help with Ubuntu or Debian setup given that it is going to take some little extra time and in exchange we all learn something. I myself use Mint and Mac OS. I see the benefit. But I can't with clear consience tell the customer that we use the time meaningfully if we are spending 30 minutes trying to set up his vpn client.
We are here to work not to spend hours trying to learn core linux features on our paid time.
What would you guys do? I told him that I would be much happier if he used some more user firendly distro. Doesn't have to be debian based. Just something kind of works.