I have a Beta model, I've had it a few years. The user interface is kinda clunky and because of the sky screens, it sometimes will fail to get a reading. Some sky conditions make the situation worse, if it's cloudy it usually works better. I've recently purchased a Magnetospeed and really like it, much better user interface and can pop the SD card out of the Magnetospeed and into the computer. I've found the Magnetospeed to be much more reliable at getting readings and no more pain-in-the-ass setting up a tripod and getting things all aligned which is especially a pain on a controlled range. The only downside to the Magnotospeed I've found is it isn't much use if you're shooting a semi-auto pistol. All in all, if you're going to be chronographing rifle loads, I'd recommend the Magnetospeed, it has done a fine job for me.