I know that the specs say that the 13" rMBP supports two external displays but has anyone used two displays with it and noticed a hit in performance? I'm looking to buy either a high end 13" or low end 15" for web development and I want to use it with two 22" 1920x1080 Dell Ultrasharp, one which will have a browser and the other will have Photoshop CC. I highly doubt I'd notice a significant hit but I just wanted to see if anyone has used a similar setup and if they have had any issues with it.