$1600-1800 Gaming Build - 7950 vs CF 7850

[doesitmatter]

I'm building a new gaming rig (I play everything, nearly all genres) and am trying to decide between going with a single HD 7950 for ~$360 vs CrossFiring two HD 7850's for ~$460. I'm leaning toward the single 7950 at the moment. Things I'm specifically looking for advice on are whether or not micro-stutter will be an issue, if the 7950 alone would be good enough on max settings at 1900x1200, and finally heat dissipation and noise. Advice/critique on the rest of the build is welcomed and encouraged, especially around cooling.

Approximate Purchase Date: This week - wanting to build in time for the Diablo 3 release on May 15th

Budget Range: 1600-1800 Before Rebates & Taxes

System Usage from Most to Least Important: Gaming

Parts Not Required: Keyboard, Mouse, Monitor, Speakers, Optical Drive, OS etc...

Preferred Website(s) for Parts: www.NCIX.ca, www.Newegg.ca (Any Canadian site, will be price matching)

Country: Canada

Parts Preferences: I have two Newegg wish lists that are intended only to show the parts I am considering, not the price I will be purchasing these parts at or their availability. These two wish lists are identical save for the different video cards. A final note is that the power supply chosen was just a quick choice - I will likely be changing which PSU I select after deciding on the vid card setup. Single 7950, CF 7850

Overclocking: Yes - as far as I can go without voltage bumps to keep Ivy's temps down, aiming for ~4.3-4.5ish GHz. Also looking to bump up clocks on the vid card(s), to ~7970/~7870 levels as appropriate, and tighten timings on the RAM if the sticks are capable, hopefully to CL7 or 8.

SLI or Crossfire: This is the real question

Monitor Resolution: 1920x1200

Additional Comments: I will be using the SSD as my OS/Applications drive, and the 3x2TB Drives will be put into a raid 5 array for my data. I will also be purchasing additional case fans for the empty slots this case has available, though I'm debating whether or not the side (window) fans or the one behind the motherboard will be beneficial, but am leaning toward adding them.

Thanks!

Parts listed in the wish lists with expected prices:
CPU: i5 3570k - $229.99
Cooler: COOLER MASTER Hyper 212 EVO - $29.15
Motherboard: GIGABYTE GA-Z77X-UD5H - $177.90
RAM: Mushkin Enhanced Blackline 16GB (4 x 4GB) DDR3 1600 CL9 - $95.25
Video Card: HIS Radeon HD 7950 - $359.99
Alternate Video Card: Sapphire Radeon HD 7850 - $231.76 x2
SSD: Mushkin Chronos Deluxe 240GB - $219.99
Hard Drive: Seagate Barracuda 2TB 7200RPM SATA3 64MB 3.5IN - $113.33 x3
Case: Antec Eleven Hundred Performance Gaming Case - $88.11
PSU: CORSAIR Enthusiast Series TX750 - $103.83

7950: ~$1,644.20
CF 7850: ~$1,747.73

 

[kosmos_oc]

I have the same problem. 7850 CF or single 7950.