WD Red 4TB NAS Internal Hard Drive - 5400 RPM Class, SATA 6Gb/s, SMR, 256MB Cache, 3.5" - WD40EFAX

Pros: The drives will probably work fine as desktop or archive drives. Price is reasonable.

Cons: Western Digital is marketing these drives as compatible with NAS systems and RAID configurations. But as multiple media outlets have been reporting, the EFAX drive models use SMR drive technology. This type of drive is known to have performance and compatibility issues with RAID and NAS configurations, including randomly dropped drives and issues resyncing. Western Digital as know "fessed up" and provides information on their site describing exactly which models of drive use SMR, but they still insist these drives can be used in RAID and NAS configurations. They cannot.

Overall Review: I would only recommend these drives if you do not plan to use them in a RAID array or a NAS unit. Western Digital needs to stop marking SMR-based drives as appropriate for this use case.

Cons: DMSMR drives offer terrible performance

Overall Review: Bought these thinking they were a good deal. They were not. They were significantly shower than CMR devices and I'm preparing to return them

Cons: SMR

Overall Review: Found out that this model uses SMR, not CMR, as its recording methodology after I purchased it, even thought it is labeled as a NAS drive. Not nice Western Digital. you just lost my future business

Pros: N/a

Cons: SMR; not suitable for NAS; shady behavior on part of manufacturer

Overall Review: I bought a 6TB EFRX drive years ago and loved it. Bought this last year to match the other drive in my RAID and immediately noticed how slow it was in mirroring the data on my existing drive. Now I find out about how WD quietly switched a lot of drives in this line to shingled recording and are telling people they should’ve instead spent more on the pro line. Congratulations, WD, you’ve diluted your brand and spoiled your reputation and good will. You lost a customer with your SMR shenanigans on NAS drives.

Pros: Can be had for pretty cheap on sale.

Cons: This newer 6tb model was refreshed as a SMR drive.

Overall Review: First one I got was defective. Bad sectors. Western digital lifeguard failed almost within minutes of running a extended scan on it. Returned for another one. Second one had no bad sectors but experienced performance issues which is when I discovered that this is a SMR drive. While being good at write to it once archive type drive. It’s comes up short if you do a lot of re writes. My only suggestion is to do a quick read about PMR vs SMR drives and find out which one is best for your application before you buy. It’s a shame that WD doesn’t come right out and say that this is a SMR drive. Would of saved me some time and restocking fees.

Cons: - When I purchased this drive, it was not labeled as an SMR drive. I replaced some conventional drives with two of these drives about 6 months ago. It took a LONG time to rebuild the array, which seemed normal enough and I was glad to have the extra space. However, it has been an incredibly slow drive ever since as I have a lot of large files that take forever to sync between by two NAS's. - Because of the slow speed of the shingled magnetic recording, the syncing seems to timeout, then it loses track of changes and I end up with duplicate files. I have done everything I can to troubleshoot this and have come to the conclusion that the only thing it can be is the drive itself. - There is currently a class action lawsuit against WD for the misrepresentation of these drives as suitable for use in NAS's. - Don't buy if you want to use in any kind of critical or responsive system.

Overall Review: Would not recommend.

Pros: There are absolutely NO pros about this product.

Cons: Refer to class action lawsuit in regards to this line of drives, using SMR technology, which is unacceptable for use in NAS applications, which the drive is specifically marketed for. Prepare for extremely long read/write times. It would be faster to ZIP your files onto floppy disks.

Overall Review: DO NOT BUY THIS DRIVE.

Pros: None

Cons: Slower than the WD Red 3TB WD30EFRX models I got 5 years ago. Louder than previous WD Red 3TB .

Overall Review: I purchased 4x WD Red 6TB to upgrade my NAS. I went with WD because of past WD reputation. Now, I cannot longer trust WD, since it will be hard to know which drives are better than others. Shame WD.