2 things, the rest mostly boils down to preference:
I've read Ivy bridge has heating issues.
HDD: Get 3 x1TB and put them in RAID 0
or 4x500GB in RAID 0 and 1TB external
I too read about the Ivy's heating issues. I'm hoping sufficient cooling will suffice but it's not that i'm planning to OC alot. Here's something I was told on another forum:
Ivy-Bridge is hot, if you ignore that it gives you 7% IPC gain against Sandy Bridge.
I will not get into benchmarks (since they have been discussed a lot on this forum) but to get same performance you need lower clocks on a Ivy chip.
For instance if you want to game on a Sandy chip at 4600MHz, you can get the same performance at 4300MHz.
But If you are OCing your Ivy chip at 4600MHz then you will get higher temps.
Keep in mind that Ivy is not a new architecture. Its a die shrink. More dense silicone = more temps.
In a nutshell, Ivy isn't bad. What matters is that either you want low temps with very high clocks or same performance with a bit lower clocks at about same temps.
Secondly: I am not at all familiar with raid XD. What is 3x1tb in RAID 0 compared to a 3Tb hdd? Also will it be compatible with my mobo and ssd?