SSD's primary (and currently only one) advantage is the speed at which you can read/write to them.
Beyond that, price vs capacity, you cannot beat traditional hard drives in comparison to these devices.
Some of the older generation drives had a finite amount of read/write operations before perceived failure would start to occur, but in all likeliness, you'd not see that happen (hopefully).
SSDs are certainly making an impact into the drive market, but as use for backup media - the costs involved just do not make them viable, unless of course you have your own money printing device!!!
As an example;
0.5TB SSD will set you back say £275
Standard 2TB HDD will set you back £70
So to get the same backup capacity as the standard 2TB, you're looking at £~1100
For the same amount of money you could get ~15x 2TB drives = 30TB of storage!!!!!
I for one would question, and then requestion the need for such a high speed storage device. If you're going to be editing an image (or even a few), then yes, use an SSD to copy them to whilst you work on them (but even that will be overkill in most cases), then save the edited images back to your normal backup drive(s).