I'm under no illusion Ubuntu is perfect. But I PAID for my Windows licenses. And if I paid, I don't want to see ads. I don't care about Win 8's penetrative pricing model or the $25 coupon. I don't care that I paid for my licenses 10+ years ago. Don't sell me ads on a product I paid for. And Windows serves up ads all the god damned time now. If there's anything good to be said about Windows 8, it's that it didn't take every opportunity to sell me an Office 365 subscription ever second breath I took. I don't actually remember the last time I saw an ad in Ubuntu, and I've been using it to varying degrees since 2011. I think we can at least agree Canonical is better than Microsoft, yeah?
All that said, I've had thoughts of switching to plain old Debian, especially now that I'd consider myself much more experienced and comfortable in Linux. But if I were recommending a distro to a new user, I am one million percent telling them Ubuntu or Mint, depending on how they feel about the Windows UI.