Nictrix said:
Surely this will aslo mean an extra cost when replacing tyres as the valves are normally replaced along with the tyres.
Cant see many people wanting to add an extra £50 on top of a tyre change for a new valve though.
Valves dont last forever. A few months ago I had a valve perish,split and start leaking air on the mini, if I hadnt noticed it it would have eventually burst altogether.
Not necessarilythe same thing but I had TPMS on my 350Z (non UK spec BTW) and they gave me a surprisingly display of the pressure in psi of each wheel.
Yes, I guess they added some cost, no they didn't need changing with every tyre or indeed at any time in 6 years of ownership, they had IIRC an ally stem and were the same system as installed to Renault cars.
In my opinion a very useful item and they were a whole lot more accurate (and use) than the system on our E85/86's which is based around sensing changes to the diameter of the tyre, which to my mind is an inaccurate way of doing the job.
In my opinion the Datsun version was far superior to the BMW version I have today whisch I think is next to useless since it didn't detect low pressures when I swapped over from fully inflated summer wheels to my winter wheels last autumn and drove to the local garage to pump them up as they'd all gone down 3-5psi!
I remember reading somewhere that the EU intended to mandate TPMS at some point so it might be due to this?
In any event I think it's worth the extra cost at purchase if it keeps me safer or gives me some level of comfort that it does!
And in the case of your leaking tyre/valve would have quickly told you which wheel had low pressure so you could deal with it before it damaged the tyre carcass let alone burst!
ETA
From
http://en.wikipedia.org/wiki/Tire-pressure_monitoring_system
From November 1, 2014, all new passenger cars sold in the European Union must be equipped with TPMS
The significant advantages of TPMS are summarized as follows:
Fuel savings: According to the GITI, for every 10% of under-inflation on each tire on a vehicle, a 1% reduction in fuel economy will occur. In the United States alone, the Department of Transportation estimates that under inflated tires waste 2 billion US gallons (7,600,000 m3) of fuel each year.
Extended tire life: Under inflated tires are the #1 cause of tire failure and contribute to tire disintegration, heat buildup, ply separation and sidewall/casing breakdowns. Further, a difference of 10 pounds per square inch (69 kPa; 0.69 bar) in pressure on a set of duals literally drags the lower pressured tire 2.5 metres per kilometre (13 feet per mile). Moreover, running a tire even briefly on inadequate pressure breaks down the casing and prevents the ability to retread. It is important to note that not all sudden tire failures are caused by under-inflation. Structural damages caused, for example, by hitting sharp curbs or potholes, can also lead to sudden tire failures, even a certain time after the damaging incident. These cannot be proactively detected by any TPMS.
Decreased downtime and maintenance: Under-inflated tires lead to costly hours of downtime and maintenance.
Improved safety: Under-inflated tires lead to tread separation and tire failure, resulting in 40,000 accidents, 33,000 injuries and over 650 deaths per year. Further, tires properly inflated add greater stability, handling and braking efficiencies and provide greater safety for the driver, the vehicle, the loads and others on the road.
Environmental efficiency: Under-inflated tires, as estimated by the Department of Transportation, release over 26 billion kilograms (57.5 billion pounds) of unnecessary carbon-monoxide pollutants into the atmosphere each year in the United States alone.