We haven't bought a HD in over 5 years. What's it for ... Gaming ?
http://www.tomshardware.com/charts/hdd-charts-2013/-17-PCMark-7-Gaming,2915.html
In order of gaming perforemance
Seagate Desktop SSHD = 9.76 MB/sec ($69.99 for 1 TB Model)
https://pcpartpicker.com/product/ftPfrH/seagate-internal-hard-drive-st1000dx001
Seagate Barracuda = 6.55 MB/sec ($45.88 for 1 TB Model)
https://pcpartpicker.com/product/dCxfrH/seagate-internal-hard-drive-st1000dm003
WB Black = 6.34 MB/sec ($69.00 for 1 TB Model)
https://pcpartpicker.com/product/Fz2kcf/western-digital-internal-hard-drive-wd1003fzex
WB Blue = 4.01 MB/sec ($47.49 for 1 TB Model) *
https://pcpartpicker.com/product/MwW9TW/western-digital-internal-hard-drive-wd10ezex
That listing is a bit unfair as the 500 GB model was slower than the 1 and 2 GB models as the latter had greater areal density. But it certainly was slower than the WD Black.
If not a gaming box, then you can look at other performance criteria
Application loading
Seagate SSHD - 17.25 MB/s
Barracuda = 4.20
WB Black = 4.30
WD Blue = 2.23
For other usages ....
http://www.tomshardware.com/charts/hdd-charts-2013/benchmarks,134.html
As i said, for the last 5 years we have used nothing but SSHDs in both laptops and desktops... so far not a single unit has failed. Those we own are used mostly in workstations with primary usage being AutoCAD. The ones we build for others are either installed on municipal offices, engineering forums or gaming boxes.
Before that we used the Barracuda 7200.14's, 7200.12s ... some of these are still in use as portable backup drives which are stored off site. We also had a few WD Blacks but saw no measurable difference in speed or reliability ... Seagate drives are relatively easy to return for exchange under warrant ... we returned one... oh I guess in 2003 or so. Delivered replacement, next day and we sent failed drive back in same box new one came in. We did pay for the ON mail but not the return. WD failure was in I'd have to guess 2006, they were not very helpful. They would not ship until getting old one back even with credit card. We shipped overnight, they sent snail mail... overall downtime was 6 days. As for who changed what policies in last 10 years, I have had no experience... haven't had a storage failure in about 10 years.