Thread: Upgraded HP Z420 - sufficient for AE CS6?

I work for an IT company and therefore can get steep discounts on HP and other hardware (cheaper than DIY build).

Here's the setup I'm looking at. The main purpose would be CS6 video and motion graphics editing. I am a beginner, but learn quickly, and plan on getting more advanced sooner rather than later. Want a system that will last 2+ years w/o upgrades.

HP Z420
-E 1620 3.6 Ghz Quad-core Xeon processor
-UPGRADE 4x4GB RAM (16GB total)
-UPGRADE 500GB 10K SATA III drive (boot drive)
-UPGRADE 2x2TB 7.2K SATA III drives (2TB total RAID1 storage)
-UPGRADE EVGA GeForce GTX 570 2.5GB Graphics Card
-2x HP 24" LED-IPS monitors

I can purchase all this equipment for roughly $2400 after discounts, so have a good incentive to purchase the name-brand equipment.

Questions:

1. Will the CPU suffice (is higher-speed QC better than lower speed, 2.8, 6C?)?
2. Are my memory specs sufficient (regular & video)?
3. Does my HDD configuration look good? I want a boot-specific drive, and would also like a RAID1 storage drive (I have 3 total HDD slots to work with)

Thanks for the help!