Update on Feb 2016
After having an NX200 for 14 months now I came to the best headrest solution for me. I realized it was more than just the headrest, it was also the weak back support. Such a waste of an expensive seat and design. Errr. I worked as a physical therapist in the past and have great posture and health. This NX200 seat and headrest and the worst and make me slouch, which I would not stand for. I ended up putting the headrest from the back seat on the front seat and buying a McCarty's Sacro-Ease Deluxe Model Lumbar Seat Support with Extra Padding, 15-Inch Wide, Black for $200 on amazon. I have full 5-point harness kid car seats in the back so no headrests are needed in the back. I tried many other ideas to no avail, including ordering a new driver's headrest for $750 from my local dealership, via Japan (was too hard to modify so I gave up). I sure miss my 2006 year 400RX (I think that was the model, was hybrid large SUV) that I sold for $12k to buy the NX200 for about $45K. I liked my old car way better, even though it had ancient bluetooth. Next time I will likely get a BMW x3 or perhaps grand jeep cherokee.
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Post from Feb 2015
I made some progress on the headrest issue... First more of a description of the PROBLEM, then the SOLUTION.
THE PROBLEM: I absolutely love lexus service. It is 50% of the reason I rebought lexus. Honestly in hindsight I would have bought an x3 (like my wife) simply b/c of the headrest issue. The driver seat is just not comfortable for me. Now I am bent on fixing the issue for peace of mind and to relax my body. I have great posture and stretch everyday to stay relaxed. The NX200t headrest makes a person with good posture more tense and is not ergonomic. Additionally the bucket configuration is built for slouchers not ergonomics/healthy back. This article perfectly describes the reason why the seat is bad including the headrest http://www.yogaback.com/car-backrests-headrests-4-design-fallacies-causing-back-and-neck-pain-driving.html What really annoys me is that for this model car, does have an adjustable headrest (forward/aft) available outside the US (as indicated in the handbook), but not sold in US b/c it was not safety tested. Other lexus models do have the forward/aft adjustment, like GS.
THE SOLUTION: Order an adjustable headrest (forward/aft 4 positions) from canada, UK or last choice japan due to language barrier. This will fix the headrest issue. To remove the slouch in the back I ordered yogaback from http://www.yogaback.com/The_YogaBack_for_Driving/new_YogaBackDriving_BU.html I tried a couple other back supports, like McCarty's sacroease, but like yogaback better, plus has a better price. The store owner also sent me a strap for yogaback to keep it in place.
I am on the hunt at the moment to special order the forward/back angle adjustable headrest. If I can order it, it will likely take a few weeks. I will report back in a few weeks on whether I was able to order it and tips for doing so.
TEMPORARY FIX: Temporarily I switched the leftside backseat and driver seat headrest. I then turned the headrest backwards and added a carneck pillow to fill in some empty space http://www.amazon.com/dp/B00A7ZV0R0/ref=sr_ph?ie=UTF8&qid=1423664014&sr=1&keywords=pillow This alone makes it 70% better. I had tried every combo of turning headrest forward/backward in the car and found this was the best temp. fix.
GENERAL NOTE: It looks like across US auto manufacturers bad headrests are now often an issue. This is because they are designed for a driver who slouches and safety tested fro slouchers. How aggravating for non-slouchers. it is the exception to find a headrest with good ergonomics. BMW has them and some lexus have adjustable forward/aft, but not all lexus as I found out the hard way.