Thought I'd post this here because questions about hard drives and Sonar come up fairly frequently - some nice info about brands and reliability. 
 
http://blog.backblaze.com...rd-drive-should-i-buy/

For a Os drive 256g ssd : Samsung 840 Pro Series 256GB 2.5" SATA 6Gb/s Solid State Drive (MZ-7PD256BW)   or
                                   : Samsung 840 EVO 250GB 2.5" SATA 6Gb/s Solid State Drive (MZ-7TE250BW)
 
For data drives              : Seagate Constellation ES.3 1TB 3.5" SATA3 7200RPM Hard Drive
Part no: ST1000NM0033
 
 
Have a good day!

Oddly, the data shows Hitachi as most reliable and Seagate as least reliable, but the author sums up by sayng they will be going with Seagate.  So, I am not sure what the message is here.

I guess reliability isn't everything.....

I have a 128 Gb SSD for windows and sonar, 512 Gb for games, and recently got a pair of 4 tb seagate HDDs due to my 2 Tbs getting full.

The operational use of a drive also plays a great deal into its expected life. Server banks versus PC usage are dramatically different. Google published a similar, more comprehensive, study in 2007, which was also based on server usage of drives, but they also defined "failure" as "the most accurate definition we can present of a failure event for our study is: a drive is considered to have failed if it was replaced as part of a repairs procedure." People running servers treat drives as expendable, so at the first sign of "anything," they will swap it out (i.e. "fail" it) just to be safe and keep server banks online.
 
There are a lot of nuances that can play into "reliability" of a HDD, so the operation and maintenance of the drive also take a large part in this. Many of the drives mentioned were not designed specifically for server usage, they were designed for desktop usage. Very different environments, so take papers like this with a grain of salt.
 
I don't want to delve too deeply into this, but the big thing to steer clear of has already been mentioned in many threads... "green," low RPM, and drives not SATA III stay clear of... the reason the heads in those drives are there is because they do function, just not at the data rates needed for 7200+rpm.
 
Edit: As far as SSDs, the above recommendation is sound (Samsung 840 Pro Series)... check out the benchmarks of the top SSDs and the price point at the right!! Shop wisely!! (or risk paying 20 times for something half as fast)
 

2 and 4 Tb drives were initially released at 5400 RPM, I've been through a pair of both and not had issues.

7200 RPM was no longer important as I was using SSDs for anything that needed speedy loading.

konradh
Oddly, the data shows Hitachi as most reliable and Seagate as least reliable, but the author sums up by sayng they will be going with Seagate.  So, I am not sure what the message is here.

I noticed while looking at the Annual Failure Rate graph that the Hitachi bars (the red ones) although shorter, have higher numbers. At first I thought fewer Hitachi drives were failing when I interpreted the graph visually, but then looking at the numbers, it seems more like they're failing four times as often (or perhaps four times the data is being lost) as WD.
 
What's mysterious to me is that they aren't going with WD Red which, according to their data, are the most reliable drives; perhaps it's because of the cost. I've always had good luck with WD, even after they were bought out by Maxtor and various places I've worked have used nothing but WD. I've used nothing but WD Black drives since they came out, although I'd be using the Reds if I had the dough.
 
Interestingly, though, one of my WD Black drives did die, a first-generation 1 tb model. It was under warranty, so it was replaced at no charge and the replacement has been working fine for over a year. It must be 2nd generation.
 

I always used to buy Samsung drives, but they were bought by Seagate. WDs are significantly more expensive though they have longer warranties.

I'd like a larger SSD to replace my 128 Gb, but I spent my PC budget on Sonar X3 so it wont be happening for a while, but the longer I wait the better I can get.

 
I'm not sure where you want to go with this, nor where everyone else is going...
 
For an SSD, why not go with the king, Intel ?
 
For hard drives, as far as I'm concerned, WD is the top of the heap.  VelociRaptor for the extreme, black for the rest.
 
Hard drives are so cheap now, it's ridiculous.