I played the Beta on a 7200rpm HDD and now play with the whole system on SSD. The load times for crossing zones definitely improved, but I don't feel any difference in actual gameplay. And in case you didn't know, during beta the game had a slower tick so many many people were having trouble dodging AoE because they'd be outside of the red zone for half to a full second and still get hit. I never had that problem.
I would recommend an SSD for any of these reasons:
- You have a liquid-cooled or otherwise super quiet system and the sound of your HDD motor spinning and the head moving around is driving you nuts.
- Your system (doesn't include peripherals like display, keyboard, mouse, speakers, etc.) is costing you more than USD$1000. Then why not. Might as well go the extra mile.
- You spend a lot of time on your computer, not necessarily just playing FFXIV:ARR. You will feel the SSD improvement the most in non-gaming related usage scenarios.
- You are at least putting the whole operating system on the SSD, and you will buy a big enough SSD that will hold all of your most frequently used stuff. My 120GB ended up not enough for my broad interests and now I run a 500GB SSD.
- You have already decided to buy a new disk, just trying to decide between HDD and SSD, and you don't mind the price difference.