The problems with Linux as a replacement for Windows or Mac are that the fundamentals are not there. Recent hardware support is non-existent as volunteers have to write drivers so you're likely stuck with old hardware. You'll get anecdotes of people who are happy with what they have, but any such person that I've known long enough I've seen them gripe on IRC about things that are completely trivial or just not even issues on Windows or a Mac.
Linux needs a hero with deep pockets that builds their own hardware and drivers. I thought Dell might have been that hero once, but it never became a priority for them.
If you could get elementary OS working on a nice slim, powerful Samsung or Thinkpad laptop, with good battery life and driver support then I'd think you'd really have something.