I recommend these two NX safety clips for your review, especially the 1st on the pre-collision (radar) system in operation.

https://www.youtube.com/watch?v=zTSs5pwtzh8

https://www.youtube.com/watch?v=qs8LqCYXpO8

Great video's, good way to get a good sense of what it will perform like in real life situations.

Thanks for posting these, they are posted below, embedded:

I just drove my NX to So. Jersey from CT on Saturday via the Garden State & NJ Turnpike. Normal NJ driving gave the pre-collision system plenty of exercise ... it hit the brakes several times. But, given that environment, I would not recommend it. There were a few times where drivers behind me were clearly surprised by the abrupt slow downs the system made. Nothing beat real defensive driving in expecting the unexpected. The drivers behind me clearly had no concept of watching drivers ahead of me either.

As it was my 1st real test of the system, I let it run at the default detection distance. On the way back I reduced to the mid distance and seemed slightly less eventful to the rear even tho the gap between myself & the car in front became slightly more eventful.

There were a few other little anomalies such as across 3 lanes of traffic with slower cars in the center. The system picks up on the slower cars which could make you a hazard for the faster moving cars in the lane you are moving to. Sounds obvious I know, but the slow down can be quite abrupt.

Conclusion is that I think it is a very good feature, but requires an adjustment to driving technique.

Thank you for your experience with the system. On paper, it seems like a great feature to have to prevent an accident. I would like to get it on my next car.

These systems should become pretty standard soon. I read that crash testing will start to consider the system as a part of their ratings. I think that this will proliferate to more mainstream models pretty quickly.

Thanks for your feedback from driving one yourself.
On the plus side to those flaws, with a system like this I think it's possible they can fix those flaws with some testing and tuning and then maybe it's just a matter of a software update to make it run more smoothly?

Doubtful...my Prius v with PCS and radar cruise behaved the same way as above. And that was 2010. It may be software, but i fear that it is hardware limited (camera, radar, processing chip, etc.). Either way, i think that the next gen of PCS will be improved upon thru hardware & software.

In these things, Lexus tend to lag behind the Germans...and sometimes for good reason as other brands test new techs and fixes bugs for them.