memory is cheaper :P besides it will come in handy playing other games offline
sdd is slower as normal ddr3 memory too only drawback is if your get a system crash.. all in memory is lost lol unless you autobackup memory every now and then to hd
the new mainboards support up to 128 memory , i think 32 gig will be great and not expensive at all.
The only drawback is you need to load the total image of the game in memory each system (re)start.. then again i mostly use Hybernate so its a lot faster