Good deal. All except for the MIR. At the risk of being a negative nelly, these are just getting worse and worse. For those that are unaware, they don't even send you a cheque anymore. You get some lame prepaid AMEX card that starts decreasing in value after 6 months. You can't even use these things at many restaurants b/c they try to authorize a greater value than the purchase...
Anyway. Boo on MIRs. Yay on HD 7970s for ~ $300. Though they seem to have gone up a bit this week, for the last couple of weeks you could find a couple of HD 7970s for $300 without having to mess with MIRs.
Also, I would personally avoid XFX HD 7970s as those double D coolers are some of the worst of the after market HD 7970 options.
Edit: Actually, you can currently get this
Sapphire for $300 without MIR. Or if you prefer a reference PCB (for those that might want to water cool at later date, etc)
this HIS is a good option, also for $300. (both with better coolers than the XFX)
I just picked up the HIS myself, and it's been pretty good. Overclocked to north of 1150 Mhz with a modest voltage bump. Cooler keeps it well under 80 deg at 1150 MHz, though it does get a tad loud when at full GPU load. Clocked down to 1100 Mhz, the thing stays very quiet and doesn't go much over 70 deg C.