There's so many text based editors to choose from, and I've used most of them now, including Scrivener. It really comes down to what makes the most sense for you, your writing goals, and your budget.
Word
Has the benefit of being the de facto standard upon which all others are based. Very powerful editing tools, but can get costly for the individual. Though I will say that if you got a new computer, you really shouldn't need to re-purchase the license as this can be re-used wth a simple call to Microsoft. The application is also cross-compatible across many operating systems.
The historical pricing model was it's downside in that it was not very cheap to get or maintain if you needed to upgrade to a new version. As many companies are moving to cloud-based licensing, and the ability now to get multiple software applications as part of a yearly subscription model has kind of changed the game here a little. For a meager $70/year, you can get a base model of Office 365 which includes Word, Excel, and PowerPoint. For that price it really don't seem that bad, but you are locked into a recurring payment.
My biggest complaint though here is that because Word has become the de facto standard, it has evolved to include many many functions. As with any software application, the more functions it houses, the heavier and bulkier the footprint becomes on your work station. I have often found Word takes a long time to load, save, and even refresh documents that are large.
Overall though, for the now cheaper price, I can see the value in using Word over other editors. Take this with a grain of salt though, because my day job pays for my applications and because of that, I can install on both my work and home computer legally without incurring an additional charge, so it's easier for me to sing the praises here. That said, there are other options out there that have certain appeal.
OpenOffice
This is an open sourced version of Word. It has the benefit of being both free, and most of the characteristics of Microsoft Word. The downside is that if you are used to MS Word, it does require learning a new user interface (UI), but enough is similar to get the majority of people through probably 90% of what they'd done in the past.
LibreOffice
Similar to OpenOffice, though this is the one I've not really used to any great extent. I tried it on a Linux box during testing once or thrice, but never really got serious into using it as my primary editing tool.
Pages[
The nice this about Apple's Pages application is that it not only comes native to the OSX platform, the UI is a smooth seamless and intuitive add-on to the entire Apple experience. If you grew up on Apple, the interface is very easy to learn. It also syncs well with iCloud, Dropbox, Google Drive, and other cloud based services, with iCloud being obviously the most seamless of the three mentioned. My personal nit here is that it does seem a bit heavy in its templates, which ironically is also my nit with Microsoft Word. What this means is that if you try and copy/paste it from the native application to anything like Notepad, EditPlus, or some other true text-based editor, code starts showing up in weird ways.
Scrivener
I am relatively new to the Scrivener interface and design, but picked it up fairly easily. Now granted, I am probably considered by most to be something of a power user, so learning the interface was likely a bit easier for me, but the combination of features and the low cost of entry for usage is pretty sweet comparatively speaking to the standard gorilla of Microsoft Word. Now that even Microsoft has moved to a subscription based service, the price of $70/year for the entire Office suite of Word, Excel, and PowerPoint isn't as bad, but if you don't use the latter two, then it's a bit overkill. Scrivener does everything a writer could need and instead of a recurring license, its a one time cost. One of my favorite features here is that not only is it a one time purchase deal, I also love how small the footprint is. It takes up very little in the way of storage space, loads quickly, and is just a robust, smartly designed writing tool.
Google
Docs
The advancement of cloud based services like text editing, spreadsheet like functions, and such have all come on the heels of the original cloud-based tools developed by Google. It's super slick when you need to share files and collaborate with others, because everything is available to everyone all the time. It does start to become sluggish, as others have mentioned, when either the file size gets heavier, or when there are a lot of people "collaborating" at the same time. I also am not a huge fan of cloud-based services that let you get up to 2-6GB of data on there, then say "Hey you're almost out of free storage, so sign up for our paid services."
It immediately raises red flags as kind of a bait and switch mentality, but I get the business model, and in reality, when you consider that Google is really an ad-based company, and they deliver advertisements to you based on your search history, web pages visited, and now email content, I believe it's only a mattter of time before they start scanning your online documents and start sending you ads based on that content. A little too big brother-y for me...of course I say that while still having about 6GB of data on their service, and still use their email daily even though I told myself I would stop and move to a more secure mail service, so take this review here with a modicum of a grain of salt! LOL