OWC Mercury Elite Pro Quad RAID Ready (JBOD) 4-Bay Storage Enclosure

I've owned one of these for 2.5 years and it has been so perfectly reliable that I bought a second on Amazon 9 months ago. Unlike some other devices I've used, this one works great with whatever I put in it and has never disconnected unexpectedly.I've used it with large spinning disks (18 and 20 TB IronWolf Pros) as well as SATA SSDs (Samsungs in 500 GB and 8 TB sizes) and everything in between.I didn't buy it with the RAID software as I didn't want that feature. I'm using it with a M1 Mac mini that functions as a home server, mostly running Plex to serve my media, DVRing over the air content, and acting as a Time Machine target for a laptop. Not the end of the world if this thing loses a disk and goes down as I've got local and online backups of everything.

Emits a constant electronic fry buzzing noise, which is loud enough to hear from across the room, and in fact from outside the room. The noise is nothing to do with the drives in the machine, and doesn't change when you install drives. It's a PSU noise, not a fan noise.OWC reps here on Amazon and on Reddit advised me that this is NOT normal, as did a Reddit consumer with the same drive, and Amazon sent me a replacement but it did the same thing. I even bought one elsewhere and it buzzed too. Interestingly all three units had very similar serial numbers.I had to reach out to OWC email support to share sound recordings of the issue, and after a week or so of troubleshooting, OWC changed their tune and said that the noise WAS normal after all.I hate reviews that say "I'm an expert in such and such and let me tell you…" but I need to give some context for why I think OWC are being disingenuous here and have a problem with at least a batch of these things: I've run servers, NAS, and DAS systems at home for decades. And as if I didn't nerd out enough at home, I also work in the IT industry and as part of that have been on site with numerous customers over the years, large and small. I know what a home server setup sounds like, and I know what a massive data center sounds like; there's always noise, of course. Fans and drives have moving parts and move air around. Magnetic heads moving across a drive platter aren't silent. That's all fine, unavoidable, expected, and generally a smooth background noise. But this is electronic fry, out-and-out. It's nothing to do with the fan, and it's nothing to do with the drives. It's most likely a cheap or defective PSU, though that's a guess.And so I'm writing this review to warn others to careful with this unit at this time. I'm hoping, based off the serial numbers being so close and some of the feedback I got before OWC decided this wasn't a problem after all, that this is just a bad batch, but BUYER BEWARE, as they say.To be clear: OWC make good hardware. I've been really happy with them for years. And their staff I spoke to through the Amazon messaging system were top rate and super helpful. But ultimately once I got to their direct email support, they started saying that this product doesn't have a problem. But IMO it does.I have to recommend against buying it. If you can put the unit in a separate room, you might be able to ignore the noise (and I considered this myself), but the nature of the noise has me concerned that the PSU will not last as long as it's supposed to.In the end, I ordered an OWC Thunderbay 4. It's a beautiful machine and makes normal drive array noises. It's got a way higher throughput than I need, and costs more than I wanted to spend, but at this point I just need to stop trying to get the Mercury Elite Quad Pro to work for me. I hope others have a better experience. I'm a bit disappointed that some at OWC want to sweep this under the carpet, but I'll get over that.

Clean design, same color/feel as aluminum Apple products, plenty of air circulation. Would buy again.

Bought two of these units for long term storage for a several Macs in our small audio and video enterprise. I loaded one of the 4 bay units with four WD Red Plus 14TB drives configured as two Raid 1 mirrored drives. The second unit was configured with just two WD Red Plus 14TB drives (two empty bay for future expansion). The assembly was quick after watching one of OWC's installation videos--which probably wasn't needed if like me you've built a computer or assembled an external drive before. As always, follow instructions for installation of both the enclosures and the hard drives. For example, wear a grounding strap when installing the drives. The units powered on immediately and I was able to easily format the units for use with my Mac computers. I chose to forego SoftRaid on either of these units--based on my specific needs at this point, but also because of some of the negative reviews I'd read about the long term cost and reliability of SoftRaid. Both units have run trouble-free for the past month. Besides long term reliability, I was concerned about how quiet the units would be, the amount of vibration I felt (both units sit on desktops relatively close to the computers they are attached to) and operating speed. The units are very quiet and relatively vibration-free. After I assembled the units and attached them to Macs on my network, I had to copy a large amount of data from several Mac and smaller external drives. This took about as much time as I had anticipated and the even with this relatively heavy amount of writing taking place, the units remained quiet and relatively cool. It's too soon to talk about long term reliability but based on reviews of the OWC enclosures and the WD Red Plus (enterprise level hard drives), I am hopeful. I will update my review if my experience suggests otherwise. I think this combination of enclosure and drives provides an effective low cost, reliable long term storage for our video and audio data.

One of the better mechanical designs in this product space.Power supply is inside so you only need a standard 3 prong wall to device cord.Drive can be noisy because it’s front panel vibrates when you have spinning drives inside.I have put in SSDs only as a result the the supply seems to have no trouble running 4 10TB plus drives ( I did this before the SSDs).