I just wrapped thermal tape around my SSD and the standard Mac Pro caddy, been using it for a couple of years now without any issues. Sounds silly, but the SSD is so light I could probably have ignored the caddy and just connected plugged the SSD straight into the connector, but I figured the thermal tape will stop it from wobbling free with fan movementI had an Icy Dock 2.5" to 3.5" adaptor that was faulty and the drive simply didn't show up at all. I had to return it.
I now have an OWC bracket that allows the drive to connect directly to the Mac Pro's connector.
I considered the Raptor mounts but the few that I found were expensive and SSDs run so cool that I figured I didn't need it.
Wow. $8 each is an amazing price. Cheaper than any other adaptors I've come across.