Christopher Shaffer :
The higher price usually has a lot more to do with data integrity than it does performance. The surveillance drives targeted for use with always-on cameras and audio recording need to perform consistently with little room for failure due to wear & tear; so they need to have quality moving parts, better tolerance on the manufacturing specs and survive for a higher number of read/writes more so than be fast.
I don't think this is the right solution to that problem. I just put together a security camera system recently. The software supported initially writing the video files in one location, but archiving it in a different location. I so put a SSD and regular HDD in the system. The video received from the cameras is initially written to the SSD. After 3 days it gets archived (in batch) on the HDD.
1) You don't typically think of SSDs in this particular application - there's no need for blazing speed. But there is a need for constant concurrent writes to multiple files, which is something SSDs do a lot better than HDDs. I initially decided to go with the SSD because I noticed the computer frequently stuttered and lagged during competing read requests from the original HDD.
2) The HDD only gets written to about 4-6 times a day. At all other times, it goes to sleep. So I just grabbed a consumer "green" drive. The HDD is going to get less use than a home desktop computer HDD. Freeing your archival storage from the performance requirements of recording video means you can get a lot more storage for your money.
3) The write durability of a SSD might seem to be a concern. But even worst case if the flash dies after 500 writes, the 256 GB SSD can survive 128 TB of writes. I'm generating about 35 GB of motion-activated video per day, so that will last 10 years. If the flash lasts a more realistic average of 1000 writes, it'll last 20 years. I can live with replacing the SSD every 10-20 years.
4) But SSDs are expensive! The $170 cost of the SSD was trivial compared to the $3000 in cameras, cabling, and installation. The same could be argued for the cost of these WD Purple HDDs, but why pay for that sort of performance and durability in the entire
storage system. You really only need it in the portion of the system which is continuously being written to. Most of the rest of your storage just holds the video files for ~100 days.