I bought a 15" rMBP a month ago, luckily it had a Samsung screen. Then I bought a 13" rMBP. I don't know what screen it had, the EDID is masked. I ran the checkerboard test on both of these laptops and got zero retention after 15 min. on the 15" but got very noticeable IR on the 13" laptop which took minutes to dissipate (it was really bad, I mean damn!). I had that 13" only 4 days. So it doesn't take 3-4 months for IR to show up in all cases, you can definitely have it right out of the box as I found out. I took that laptop back to the Apple store as fast as I could drive. Instead of getting another 13" I got another 15" (yes, I need two laptops, it's not important why). I got the 15" instead of the 13" this time around for two reasons: The difference in portability is not huge (in my case/opinion, ymmv) but mainly because a 13" with 8gb ram, 256hd and I5 dual core costs damn near the same as the 15" with I7, quad core 256hd and you get the extra graphics card too. For some odd reason, they only charged me $2 extra. I was expecting to have to pay $100 more. The guy said the total was right so I shrugged and paid the man the $2. The price point between the rMBP 15 and 13 is weirdly small. Either you're getting a good deal for the 15 or taking it in the shorts big time on the 13. The 2nd 15" has an LP screen, darn it. I know it's only the 1st day but I ran that checkerboard test for 15 minutes and didn't see even a hint of retention. In all respects it's fantastic. No pixel problems, no color tint, and it's damn bright. Could it be that the new LP screens are fixed? Can I hope that since I don't see even the slightest hint of IR that I might be safe even later on? Do I need Apple Care to get the screen replaced if IR crops up in a few months or will they replace it regardless?