Well, from what I heard is that OLED has lower lifespan and suffer from burn-in. But still.. I'm not sure how bad this situation is. It all depends on your requirement and budget. If I were to look for a 55" 4K TV, I *might* just wanna splurge and get a $5.5K OLED. And if you're looking for a 1080p unit, you might just as well get the OLED ($2K+?).
I'm hunting for a 65" 4K unit and I rather just get the SUHD for $5.8K instead of the $9.7K OLED.
And also back to requirements.. OLED blacks are perfect. BUT, do you really need that perfection? Do you watch TV in pitch dark conditions? I've tested the SUHD JS9000 in pitch dark room and I was pretty happy. Not perfect.. but impressive. The top and bottom black bars are almost non-existent for anamorphic content