This is my 250th post on this forum and to celebrate this milestone in my "career", I thought I "vent" my views on all the I-have-a-problem-with-my-Joomla-on-a-PC-hosted-website topics that I read here on an almost-daily basis. From the outset let me say that the forum here is excellent but, while people help here with all manner of webcraft-related issues, assisting Joomlaphiles with problems that exist in their own private webiverse is an incredibly difficult task to do via a forum.
Everywhere I travel, whether it's in my own local JUG or attending national and international conferences relating to Joomla, our community seems to be divided on the necessities of designing, developing, building and testing websites on a PC-hosted platform and then deploying it on a "real" server. I meet people who are more than passionate about their use of PC-hosted sites; they're almost obsessive-compulsive about it. Whenever I challenge their beliefs—sometimes bordering on fanaticism—about the requirement to undertake their craft in a one-person "world" (usually one solitary personal computer that's not networked to others), I'm met with the resolute response, "This is the only way and you can't tell me otherwise!"
Having worked in this industry for nearly forty years before I retired, and (about eight years ago) I looked into Joomla as a means of maintaining my IT skills, I am aware of the benefits of prototyping—establishing a proof-of-concept—to establish the feasibility of a new idea. Before I built my first Joomla website, I purchased a book on the subject—my Joomla library has grown a lot since that time—and that book recommended installing XAMPP (or some other equivalent software) as a means of helping people get a leg-up to adopt this great CMS software used by millions of people today.
So, yeah, I installed XAMPP, worked through a basic install and then ... I ran into problems. Networking XAMPP across your own private LAN, dealing with the vagaries of Microsoft's firewall, but (Oh, dear Lord!) it was painfully frustrating! Still, I persevered for a few weeks learning as I went about Apache, MySQL and PHP (and wonderful tools like myPhpAdmin), FTP and all the other things we require. I couldn't believe the liberation when I saw my first site appear on a "real" server on the internet. It was almost like someone witnessning their first [two-page] novel going into print!
Undoubtedly there are benefits to using a localhost-served proving ground, perhaps in the event that something goes awry in a real internet-hosted website or if you're trying to migrate a 1.97 TB J! 1.0 site to J! 3.5, but how often do most of us really require this contingency? I suspect that there will be people reading this essay who will say "You're wrong: xAMPx is a "must-have" to build/test/fix Joomla websites."
In eight [plus] years of using Joomla, I don't think I've revisited XAMPP once. I do my development exclusively within an internet-hosted environment; I must have built hundreds of test sites—places to do that proof-of-concept that I mentioned earlier. I can usually get a "real" site up and running within a day or two ... and, if I have problems with it, I can share it with others instanteously over the www. Perhaps I'm the odd-man-in-the-room?
When I browse the topics in this forum, people struggle with questions like "my localhost site works but the copy of it on the internet site doesn't" or "my internet site works but my localhost copy doesn't". Other people then launch themselves into those topics with all kinds of advice—that has nothing to do with Joomla—about how to use "brand-X" software. Really? Is that what we're all about?
As I say, I am aware of some usefulness in a localhost-based testbed but its usefulness is limited. In many cases (unless you can afford the luxury of having total control over the target environment where the site will ultimately be deployed) the localhost environment is quite different to its "real" counterpart: the hardware is [invariably] different, the mix of end-users is different, the software may be different and the "visibility" thing—"can other people see your site"—is totally different. That's why I wonder why we spend as much time as we do helping people work through their difficulties in their own private webiverse. Perhaps I could sum it up this way: if you choose to use "Brand-X" localhost software then, when you have problems with it, go to the people (or a forum) who specialise in it.
Don't get me wrong; the assistance we receive on this forum is fantastic. But I do get frustrated when I read a topic that begins with "My Joomla site has problems" only to discover (25 posts down the track) that the person having the problems can't share their experience with the world because their site doesn't exist beyond a piece of wire extending from their office/bedroom/closet.
Would I use a localhost platform if my site(s) was/were broken beyond all redemption? Perhaps, before I slit my wrists in total desperation, I would ... but a bit of personal blood-letting isn't necessarily a bad thing, sometimes

For what it's worth! Cheers!