Seems like the cheapest as of the moment.
Information taken from a previous deal.
Headphones:
Frequency Response: 20Hz – 40,000Hz
Impedance: 32 Ohms @ 2.5kHz
Sensitivity: 109 dB (± 3 dB)
Drivers: Custom 50mm neodymium, matched pairs
Microphone:
Type: Omni-directional
Impedance: 2.0k Ohms
Frequency Response: 100Hz – 10,000Hz
Sensitivity: -42 dB (± 2 dB)
Wireless:
Type: CORSAIR SLIPSTREAM WIRELESS 2.4Ghz
Connector: USB Type A
Range: Up to 60 feet (12m)
Battery Life: Up to 20 hours
USB Charging Cable: 1.5m
3.5mm Stereo Cable: 1.5m
The corsair slipstream wireless USB dongles recently got a firmware update that greatly increased the wireless performance of these headsets. Usable wireless distance was one of their greatest short comings but the firmware update has improved the distance 10 fold). At this price these are an absolute steal.