I bought from an online deal (maybe old stock clearance) that is no longer available (it is cheap but there is a risk, thus the price cannot be compared). You can find it at ebay/lelong/aliexpress or some accessory shops. For installation in KL, it is basically RM10 per tyre. Penang not many tyre shops are doing it (I asked 10 shops and only 1 shop is doing).
I got tyre puncture a few times for my previous car, there is 1 or 2 times the tyre cannot be saved anymore although it is new (Didn't realize and keep driving until I heard very loud tyre noise). Unless you are an experience driver who are alert and notice as soon as something is not right, otherwise installing TPMS is a good safety feature.
Reason for installing TPMS that I found online:
Protection in advance:TPMS directly monitors the Tire's pressure and temperature.when the tire show an abnormal sign,TPMS can Promptly notice the driver to do some corresponding measure to avoid possible tire burst and ensure safety. TPMS can't promise 100 percents avoid tire burst,but he will give you a 7 seconds process time before tire burst.
Extend the tire’s life:when tire’s pressure is 10% pressure value under standard,the tire’s lifespan will reduce 15%.with in-time digital display of pressure and temperature value,TPMS can help driver to keep tire the standard pressure,so as to extend the tire’s life
Save Fuel consumption:when the tire’s pressure is 30% below standard,the fuel consumption increase 15%.TPMS can help drive to keep the tire’s standard pressure,cut fuel consumption.
Protect automobile parts:if driving when the tire is not at the standard pressure(too high or too low),it will bring some abrasion to the engine chassis and suspended system.
Guarantee the normally-operating Brake System:if the tire’s pressure is not in balance,it will make the vehicle run deviate in braking,so as to increase the accident risk.
Monitor the tire in real time:TPMS can help driver control the tire condition easily at any moment in vehicle,so as to help drive to make right decision,and ensure safety.