I can tell you that any brand will not last even 5 years even with guarantee for 10 years. The warranty is not on the ability to block the heat transmission but on bubbling, de lamination, whatever ... which they did not really tell you

The cheap one may last around 1 year or so. The good one may have lasting effect for 3 years or so but you did not really feel when it start to deteriorate because your body adapt to deterioration gradually.

So, it is your choice whether to use cheaper one and change every year or to use more expensive one and change every 3 years. This is my opinion

2k for 10 years is 200 per year but say after 5 years zero effect means your pay for nothing for 5 years . I used to have V-Kool. It was 5 years warranty but on the 5th years, the 200 cheap tint can sure perform way much better

I was thinking that replacing can be annoying but removing old one and put new one is quite fast process.

Hard to say because there is no single world standard measuring performance. The TSER, IR, UV, etc rejection rate measuring method can cause misleading. As light (visible or invisible) covers a wide spectrum, one can argue that the measurement say for IR rejection probably measured at the best reading on one specific spot frequency over the spectrum.

Cheap tint use dye to color, thus will not last long and most will get discolored. The one using metal particle usually more expensive (such as V-Kool) will interfere with RFID and reduce phone signal penetration into car cabin. I use the one using ceramic since it is stable material and friendly to RF signal.

Yes 0% is stupid decision for. Following car with no visibility upfront of the car is like following commercial van or truck At least truck takes time to slow down not as sudden as the car. The driver in front can be day dreaming and suddenly brake. Hate that.

Don't remember if the sop charge for removal of old one because you are installing new one from his shop

I replaced once but it was under warranty and the film looks wavery. Removing is not difficult. They just need to spray and soak ammonia solution just like most kitchen household spray.

Each brand has several series of tint. To avoid interference with RFID, avoid use metallic dust particle type which is used in one series of V-Cool as I remembered it. Other brands also has metallic dust based tint. Best is ceramic based. The one use dye based is cheap but it easily become discolored and not last that long. Metal interfere with RF signal.

Smart Tag is based on light in IR region. Many tint claims high IR rejection rate but number can be deceiving. Since IR has very wire frequency range, many does not specify at what frequency it is measured. They probably tested it in wide range but pick the number with highest rejection. I could not remember the IR wavelength of the Smart Tag but this is why Smart Tag still operate properly even though the tint has very high IR rejection number.

Many tints do affect Smart Tag to some degree when newly installed. That is why cars get stuck at toll . However any brand cheap or expensive one will degrade like a good one after 2 years will have no problem with Smart Tag. This is the reason why even good and expensive tint feel like not blocking much of heat from sun after 2~3 years

I have used VKool and also Haverkamp (now market under KRÖPELIN brand?). In beginning you have to drive quite slowly to get Smart Tag detection. So, I just lower the window glass and shove out the Smart Tag. After certain time you will find that you will not longer need to do that.

The long warranty I believe never about the ability to block but on the appearance of the tint like no bubbling, wavery vision, etc. So, the question would be whether you want to used cheaper tint that you can change every year for best performance or use the tint that cost thousands so that you do not need to go for re-tint ever one or two years

I think it is good. Mine after 5 years I could see like watery on windshield (wavery). So, the shop replaced it for free saying that it was from bad batch, but I think it is more on installation skill. Well, if you go to unauthorized shop they will give you all kind of excuse not to replace because they can never get refund from distributor.

Just like I mentioned, it does not feel like blocking much after several years, but hard to notice when since you gradually adapt to to situation. I should go back to the shop to measure the TSER, etc.

I believe it is manufactured in Germany as claimed (no prove though ). Many branded one manufactured in 3rd countries. It was expensive when it was introduced many years ago. I could not remember but it was around 4k Now the price is more reasonable. Well, price is market driven, not the cost price, but when need to generate more sales the price has to go down.