Like the racket sensors, this gives more information. There is a reason that most colleges are expected to have automated (not HAWKEYE) line calling in the next 5-10 years, and that they play lets on serves... because there is a lot of bad calling going on. Even if this is 2-3x worse than advertised (25mm x3= 75mm, it is accurate to within 3 inches. Given that the tennis lines are 50mm, for me this is a reasonable margin as long as it is unbiased and all parties agree to use. No system is perfect, and the most advanced system in the world that has been trained with top 100 pros for example, probably isn't as accurate with nadal's or sock's crazy spin. Do they protest that Hawkeye is not as good or accurate for them? No. With regard to the stats. They are helpful, this is the year 2017. We are tracking more and more stats in all sports and using them to help identify where problems and strength really are. Do I truly believe my Zepp sensor estimated max serve speeds (135-139mph)? No, but it gives me a scale to compare against myself and something that I can work on. Just like the literal scale in my house, it is not as accurate as calibrated physician scale, but it close and it is consistent to itself so I can see how I am doing. I am not going to change anyone's opinion on this, and hope it works reasonable well. Will it be perfect, no. Will it be good or ok? maybe? Will the next generation be much better- absolutely. But the newer "good systems" like playsight use far fewer cameras than Hawkeye does, and the costs/technology are changing exponentially. I do wonder if Racket King et al only use land lines/flip phones.