I will second using RAM drives on Linux for running a Minecraft server. Ram drives will handily outperform any SSD setup, and 16GB DDR3 has hit ~$68 on sale recently. I ran a Tekkit server last year on a single 500GB WD Black drive and had constant issues with chunk loading and lag. Put the server in ram and most problems went away. Do keep in mind you need a UPS and scripts auto-backing the server up every couple of minutes to prevent data loss from power interruption. Something to keep in mind with SSD drives is that the drives have a certain write endurance per cell on them. While I don't have numbers on the average writes per second for a Minecraft server, I assume they will be fragmented and frequent with the way the server writes out data. If you have too many writes you will "wear out" an SSD far before it's MTBF.