Been running such system for years - SmarTire.com. Too bad they stopped making those for bikes. Not sure about safety of other systemts. The sensor is installed inside the rim with a metal strip going around the inside well of the wheel. I spoke with them as I had doubts about safety. They assured me that they tested their system up to 500 mph (not a typo), i.e. they spun the wheel during the test with the speed equivalent of 500 mph and no issues.
Keeping an eye on your tire pressure/temperature, and being alerted if pressure/temp deviates too much in either direction is a huge safety factor. Also being able to check your tire pressure/temp occasionally with a press of a button gives you confidence in your tires, and of course it's a huge convenience factor. I find it annoying to check the pressure manually, you need to move the bike so the valve is in the convenient place, and then after you check a few times, the pressure gets lower because you let a bit of air escape on every measurement, and then you have to add more air. All of that has been non-existent to me for the past years. Only time I had to do it manually was when adjusting it for the track day, and brining it up after the track day.
I also think that safety wise, very few will notice a leaking tire until it might be too late. So, why take a chance with your life when there is a way out? Most arguments I heard don't matter - because they all imply absence of the leak. Unless a rider checks every 10-15 min, it's impossible to catch it in time. If I had let's say 36 psi which gets to 40 - 41 when hot, and then I got a puncture and because of slow leak the pressure dropped from 40 - 41 to 32 psi, I want to know that instant.
