Garmin killer? - Athlon Optics Rangecraft Velocity Pro Radar Chronograph, 2.4 in Display

Not sure yet what the drawback is of saving $100 in getting this over the Garmin, but it is not obvious to me. Haven't bothered with the apps of either brand and use as standalone devices to plug data into other apps/software. At worst, I've seen in person, and online, a 1-5fps difference between this and the Garmin and not often on the high end of difference. Mostly they both showed within 1-2 fps of one another. Even if the Garmin is more accurate to 1-2 fps consistently, it does not justify the price difference.