Let me be clear – supported by a professional, the Linux desktop is absolutely ready for prime time. I've successfully switched folks over to it and so long as a basic maintenance schedule is provided by folks like us, the end user couldn't be happier. The secret to keeping the end user happy is to make the entire process seem as easy as using a Chromebook. From their perspective, their data is just safe, their applications just work and if there is a problem, the tech is on-site to remedy the issue straight away.
One of the objections I've heard from die-hard Windows/OS X techs in the past is that offering Linux support is simply exchanging one set of problems for a new set. My comment back to them is if this is a problem, they need to reconsider this attitude about offering Linux support. The reality is, if you keep the data backed up and mirror the partitions, there really isn't anything deal-breaking that is going to crop up.
The only possible exception to that last statement would be laptop compatibility. My response to this concern is that not every machine is cut out for the Linux desktop. Even though 99.9% of the computing hardware out there can successfully run one Linux distro or another, sometimes a PC simply isn't going to cut it. Perhaps it's some oddball video issue or something isn't cooperating at the UFI level.
Once presented with a PC that isn't compatible, the obvious solution is to explain that the computer isn't going to work with Linux. Thankfully with desktops, this is rarely an issue.
Let's take a moment to review, shall we? We want Linux to see a greater adoption on the desktop. The obvious promoter in this arena is the existing network of PC repair techs out there; the mom and pop shops. Monetarily, offering a third platform to support on the desktop makes these shops stand out from their competition, especially if they're offering Linux to home users. And finally, offering Linux on the desktop to home users means new clients for a tech that might otherwise be looking at losing their business, as the competition is severe these days.
Remember, at no time did I suggest forgoing support for Windows or OS X. Rather, I'm suggesting techs include a third platform in their virtual toolbox of client solutions. On the enterprise front, this is nothing new. But for the tech who might be pushed out of the marketplace or simply needs to bolster up their home user client base, offering Linux is a no-brainer. Linux+support=ongoing income and new client referrals.