I am waiting until around November time frame to see how prices are then. While they are falling, maybe they will be even lower around the holidays. Need to get like 50 of them and that starts to add up.
So do it a little at a time.
What I'll be doing over time is slowly increasing the amount of SSD in the mix here, and repurposing the spinny rust for other duties.
The problem, as always, is that prices will continue to fall and that at some point you've got to just say screw it and jump in. Back in 2010-2011, the price for SSD was in the range of maybe $2/GB while conventional SATA storage was around 30c/GB. Now reasonable quality SSD storage is around that price, at least if you can use something like the Intel 535 (480GB => $160).
It's still very pricey compared to spinning platters. Also SSD's have a finite life. Some members have noted that wear must be monitored closely and a drive replacement schedule followed so that you don't lose your pool due to all of your drives failing in a short time span once they've reached end of life.
Of course, endurance is an issue for some purposes. A lot of what we use ZFS for here is simple file storage, without lots of write/rewrite cycles. That's definitely ideal for "cheap SSD". Wear is of course an issue with SSD's,
but recent drives seem likely to have much better endurance characteristics overall, so depending on what you're doing with your ZFS, ...
Modern SSDs have life spans in the realm of hunderds of terabytes before they're even really at risk of failing. So I feel like for most people that wouldn't be a concern. My bigger concern with SSDs for backup storage is that data recovery is significantly harder to the point where right now it's basically impossible short of going to some professional company who will likely charge you a small fortune.
Yes, which is why it's better to spend your small fortune on a decent backup strategy.
