Retina in the next iMac? Should we be worried that it will be full of flaws?

The macbook pro with retina has its pros and cons. It's powerful like a MBP, thin like a MBA, but unfortunately, it came with its share of issues. Pretty much everything is glued together. You can't change the RAM nor the battery. I wonder if you can even change the SSD.

I'm interested in purchasing the next iMac, but I'm afraid that if it's Retina, it is bound to mess up. I'm assuming you're familiar with the "burn-ins" controversy on the Macbook Pro with could happen on the iMac.

What does one do? Buy the last-gen iMac refurbished once the new iteration comes out?