I just read through this thread and I’m honestly surprised at how one sided this discussion has been.
How much sample streaming is going on is totally dependent on your content. A drum kit will easily fit in RAM. An entire orchestra will most definitely not. So it’s not entirely accurate to say in all cases your samples will be loaded in RAM and your hard drive won’t be stressed afterwards. In fact, if you do use such large comprehensive libraries, your hard drive will be working really hard to keep up, as only initial portions of samples are kept in memory and the rest is streamed and flushed as required. This is where SSD really does shine, because random access to data is so much faster on them than from HDD. And there’s no moving parts. SSD wins hands down in this department.
It’s true that SSD will wear out much faster if your read and erase from them than if you just read from them; but that’s also what makes them ideal for libraries. Just put your data on them and don’t use them for anything else unless you need to add content or update your libraries, and there’s a good chance they’ll outlive their warranty. All electronics will eventually fail, so SDD or HDD, you’d be foolish not to keep a backup of your data on an extra external drive, or some other backup solution either way.
So as far as OS vs Sample disks, I see it the other way: what difference does it really make how fast your OS and DAW launches compared to the time loading in a big project? If you’ve ever worked in a production setting, the last thing you want to do is have customers wait endlessly for another version of a project to load up. The speed of a large sample-based project load-in is significantly enhanced by the use of SSD for your libraries.
Sorry, I had to say something…