The performance will be very similar. The i7 in the Air has a slower base speed, but Turbo Boosts to 3.2GHz vs. 3.1GHz for the i5 in the base Pro. I actually had the i7 Air until about 4 weeks ago. I lost it and used my insurance proceeds to get the base rMBP (except upgraded to 256GB). For everything I have run, the two machines have been almost indistinguishable.
The primary differences are the Retina Display and the extra Thunderbolt and HDMI ports on the rMBP (and of course the added weight of the rMBP to support the larger battery). Otherwise the high end Air and base rMBP are very similar. The Retina Display is 2560x1600, which equates to 1280x800. The 13" Air is 1440x900. However, the Pro also has better color gamut, and in my opinion the screen is significantly better than the one on the Air. In a pinch, you can also emulate 1650x1080 on the rMBP.