Had to put this one first. No OS takes up 54Gb...
Are you calling me a liar? I keep my program folders and user folders (except for the data folders) on the C:/ drive (makes making backups easier). I also kept hibernate activated because that's what my UPS uses to shut down my computer when there is a power failure to avoid losing any work in progress. Since I have 32GB of RAM (I've already peaked at 16GB on occasion and haven't done any video editing yet on this machine, so yes, I do need that much), the hyberfil.sys file takes up 24 GB by itself (and I'll probably increase the default 75% to 100% in the future; I just haven't bothered yet).
...This hurts my head to read. So your advice is no redundancy, but fill up drives as they come, so if a drive goes, all the data on that drive is gone? Is that really your advice?...
And RAID 0 has redundancy? The OP said nothing about using the three HDDs for keeping redundant files. As far as losing a drive goes, that is the purpose of having backups.
...Think maybe this is a perfect situation for RAID5?...RAID 10 is for performance with redundancy. I'd like to see you make a case for needing that performance, especially with the OS on SSD...
Where the heck did RAID 5 and 10 come from? The OP only discussed using RAID 0 to get a single directory. I never tried to make a case for performance—quite the opposite—since, for data storage, even on spinners, it's not really necessary; today's HDDs are plenty fast. SSDs are fast enough, little is to be gain by RAIDing them for the OS.
The OP was wanting to use RAID 0 so he could see the contents of the three drives in a single directory. Windows 7 Libraries is a much safer and simpler way to get a single directory from several drives.
Please don't tell me you are one the misguided souls who feel RAID is a backup. Nothing could be farther from the truth. RAID is not a backup! Let me repeat that; RAID is not a backup! Other than RAID 0 (which is primarily for increasing speed), the main purpose of most RAIDs is to provide redundancy to prevent data drive failure causing an interruption of service. Most enthusiasts do not need that kind of reliability from a computer, unlike businesses, unless running a server with massive amounts of data (and, even then, the server needs some kind of additional backup). RAIDed drives are still subject to failure from internal malfunction, such as a PSU blowing up and frying everything connected to it (it happens) or a nearby lightning strike that sends a voltage spike and current surge into the power grid and blows past any surge and spike protection one may have in place. Computers can be stolen or destroyed by disasters such as fire, storm, or flooding. RAID will not protect one's data or system in such a situation.
Data that has only an original copy in one place (such as a single drive or a RAID) is not backed up. A true backup is one that keeps the backed up data off the computer itself, such as on external HDDs or other media. A bare minimal backup scheme is one local copy and another one kept offsite (although even one backup is better than none). For every drive I have in use, I keep two local backups on internal type HDDs (my machine has one each of 2.5" and a 3.5" hot swap bays; using internal type drives for backups is cheaper, more convenient, and less bulky than using external HDDs) and one that is kept in a safe deposit box in a fireproof bank vault (that gets swapped out for updating at least once a month). To cover the gap between backups, I use a commercial (i.e. paid) cloud backup for an additional offsite backup (I use Carbonite; it continuously backs up all new content on my computer, provides 30 day versioning, encrypts all data before it leaves the computer, and does all this for only $59/year).
...Disable hibernation, tweak the page file, disable system restore, done. Make sure after you run all the windows updates you delete everything in the %systemroot%\software distribution\download folder, as well as your temp folder...
I have quite a few apps (my machine is used for content creation, among other things). I've already discussed my need for hibernation (if not for the UPS, I would disable it, losing the massive hyberfil.sys file). I've disabled system restore (restoring from backup images is far more reliable), reduced the page file to 800MB (the minimum needed for Windows dump files), and clean out all temp folders at least once a week.
...And only normal users need AV. I haven't run it for years, no infections.
Now THAT is the one that hurts MY head! How do you know you don't have any infections if you don't have something in place to detect them? Also, you can get nasties even from reputable sites. Some can even sneak in by piggybacking to a safe file being downloaded or by slipping in while shadowed by a legitimate download. Most nasties nowadays make it a point to not interfere with the operation of a computer to avoid detection. You could be on a botnet churning out spam, or worse, and never know it, no matter how good you may be (or think you are). Something could be spying on your banking and shopping activities and never know it until the damage is done to your accounts. Just because you haven't been burned yet doesn't mean you won't be. And even suggesting to others to not use an AV is highly irresponsible. That's like saying as long as one drives carefully, they do not need insurance.
Its not the fastest these days, as it only feed my ssd's @ 100mb/s 
