I'd do firmware first.
...and then the pedant in me would then write to the drive serveral times with the Intel SSD Toolbox full diagnostic feature (i.e. SSD in another machine). Then, run a secure erase from the same toolbox, then install it in a system.
Well I haven't received the ssd yet so I'm not sure which firmware it has but I just want to be ready.
Ozz, I can do what you said, I do have another computer, but is that to see if it's working properly or is to improve it somehow ??
There's no improvement, it's purely to test its operation. It's like a new HDD or new kit of RAM; IMO, it's good practice to test them before placing them in http://www.google.com.au/search?q=bathtub+curve service.
I believe Intel test each SSD before dispatch. For sure NAND is rigorously tested after production. I can understand the reason for caution, but I doubt the process you suggest would induce an infant mortality failure, if such a defect existed. It will however induce unnecessary wear on the SSD.
Updating the firmware before the OS install is however a no brainer.