Upgrading WD MyStudio II: good idea?

So I have a WD MyStudio II which came with two WD 2TB green drives.
It’s about half way full and from my experience with WD green drives it’s definitely backup + upgrade time.

Was wondering if the controller in the mystudio II is good enough for a Hitachi Deskstar raid or WD Black Enterprise upgrade? The 4TB versions just dropped so an 8TB (7.2TB actual at least) setup sounds like it will keep me going for another 4-5 years.
The thing is that two of these drives are not very cheap (maybe $850) so if the mystudio ii won’t be able to utilise the drives and provide the best performance possible I might as well get a complete upgrade.

EDIT: Using eSATA to connect to the PC, averaging 125mb/s speeds

I would think not. If you’re only half full, you’ve got plenty of expansion left. If you’re expecting one of the greens to fail, well that’s why they are in RAID (remembering RAID is not a backup solution).

More expensive drives (particularly those meant for enterprise) are not necessarily faster, interfaces being equal and all, they just typically meet a higher level of quality assurance (expected MTBF).

Now, even if the controller is limiting, if you are getting 125mb/s now, you’ll get that with the better drives (maybe a marginal improvement). If that speed meets your needs and you don’t need the space, why upgrade? Re-assess when you get closer to capacity limits.

I’m using raid 0, so no real backup.
I have had two previous wd greens fail on another enclosure after about one year of use (were nowhere near full). They’re generally not meant to be used for raid but I didn’t have the budget for anything beyond a mystudio ii.

I’m not expecting a lot in the performance department. Have heard that the deskstar gives you a sustained 150 mb/s performance as a single drive which is good enough. What I really want the enterprise class drives for is the peace of mind of extended use in a raid 0 setup. Unless that isn’t a reality either?

Ah.

Well I don’t think RAID 0 really puts any more stress on a drive than a native deployment. There are no drives that are not really meant for RAID deployment - RAID is just a data protection mechanism. With the MTBF rates of even today’s consumer drives, any additional read/write overhead involved in a RAID deployment is unlikely to make a difference to the expected practical life of a drive. That said, we both know they do fail from time to time - and enterprise drives are no different. That peace of mind is no good if your drive is the outlier and you don’t have it in a protected array or backed up. And they do fail, they fail all the time, but you never hear about it because in the enterprise world they are always in a protected array unless they are only storing volatile data.

In my 16 drive array over the last five years or so, I have had 3 WD green drives fail. Two of those I attribute to repeated power failures (which is my own fault for not having a UPS at the time). I have also had a Seagate and Samsung fail. I still have five WD greens in that array. So really, their failure rate is not over-represented and they are doing alright for me. But I don’t care if I have a failure as the array is protected (and important content backed up).

I guess what I am saying is - protect or back your shit up. Even expensive drives fail, don’t trust them with important data. Buy another MyStudio II as a backup target, or hit up Crashplan. Don’t waste your money on what still amounts to an expensive single point of failure.