This is my third meter with this design, the previous two RM400 ones did not work properly. The Steinberg version seems to work well. I would give 5 stars, but due to the display, which is really nice and large, the content disappears at an acute angle, as is the case with some LCDs, they did not include a battery in the set, although it must be said that there is a USB bluetooth for the computer included in the box, as someone no, that's a plus. The casing is, well, very pleasant to hold (RM400 is like that too), rubberized sides, light, and easy to use. Unfortunately, it is not resistant to external conditions, so you need to use it wisely and protect it somehow, because it is a delicate device. In this type of devices, the GM tube is very sensitive to shocks. Just like it happens with vacuum tubes. To sum up: I wanted Alfa particles, and in this price range I think it is a good proposition. Of course, in those that do not have Alfa, you can measure them without the housing, but I do not care about disassembling the device to measure it. Overall it's very OK.