In short, the AstroAI Digital Tire Gauge is simply a great tool for measuring tire pressure. Some details below. (Note - TPG is for Tire Pressure Gauge.) What do I expect from a "perfect" TPG? Accuracy.2. It should be convenient to use.3. Reliable and durable.4. decent price. I've been using AstroAI's TPG for over 3 months and that's what I can say.1. I don't have a calibrated professional TPG handy to determine if it's accurate or not. But this TPG shows readings that match (less than +/- 0.5psi) two digital TPGs I own (one is a built in JACO SmartPro Digital Tire Inflator Pump TPG and the other is my old TPG). This is perfectly acceptable accuracy. Especially when you consider that tire pressure can vary significantly depending on the ambient temperature, for example โ a difference of at least 1psi (for small and medium-sized tires) for every 10 degrees difference in ambient temperature. (For example, you measure your tire pressure in the morning or afternoon.) 2. The appearance of this TPG is different from most others. (Rather than trying to describe what the difference is, I suggest you test almost any TPG on Revain and you'll see what I'm talking about.) But more importantly, this TPG fits comfortably in your hand as you measure and measure Fits my car's tire nipples perfectly (no air leaks). The display is excellent, the numbers are large and perfectly visible both on a sunny day and at night. This TPG uses two standard AAA batteries (non-rechargeable). I think the only downside of such a solution is that you have to change the batteries once a year (maybe less often). In any case, alkaline batteries are generally safer than lithium-ion batteries. There is one feature that I would like to mention in particular. The default behavior of the digital TPGs I've used and read is that after checking tire pressure, the TPG display will continue to show the current readings for some time (usually around 30 seconds), and then the TPG will turn off. Checking the pressure of another tire during this time can be confusing. So on my old TPG I long press the power button to turn it off and then turn it back on. So the smart guys at AstroAI asked themselves a simple question โ how many tires do we typically check in one "sessionโ. I bet most of us routinely check the pressure in all the tires on a car. So you have implemented a simple but ingenious option: when you have finished checking the pressure in the first tire, after about 10-15 seconds this TPG resets the values just measured and prepares for the next measurement. If you don't want to check another tire then after another 10-15 seconds the display will go off completely and if you want you have that time (10-15 seconds) to continue. The second measurement restarts the TPG "Timer" and is ready for the third measurement. So convenient!(Well, maybe this feature is not unique, but it is for me.)3. Reliability - I've used it maybe 30 times and still haven't had any issues. I even checked the pressure 3 times raw in the same tire and got the same values. As for the durability of this TPG, it's hard to say at the moment, but it looks and feels pretty solid! So unless you drop it on purpose or use it as a hammer, I don't see why it can't last for years. ;)four. Price - I think it's fair for a device of this quality. Conclusion: 5 stars - clear recommendation! This is a great tire pressure gauge with an interesting feature. Update (09/13/2019): As a reviewer of this TPG, I received a question this morning regarding batteries and the battery gauge. This prompted me to do a little research... The result was a little awkward - there is NO battery indicator in this TPG, and the battery icon on the display is just fake and doesn't change its behavior when the batteries are seriously discharged. If the batteries are good, the pressure gauge is working normally, but if the pressure gauge is on and does not start, the batteries are most likely completely discharged. Thought of lowering the rating to 4 stars but decided against it. TPG still works great, and this "false thing" is maybe worth half a star, not a full one. ;)