I think this is almost a loaded question. I own three. One isn't worth mentioning. The Crony Alpha I have is fine, and works great outdoors, but I can't get it to work reliably inside even with the light kit.
Last year, I bought a L1000 Listone. It only measure in m/s, and cannot be used downrange. However, it is rechargeable, very small, and works no matter the ambient light. I have used it a whole lot.
I have a new Oehler, but I've never unpacked it. In any case, I don't think you can argue about Oehler's quality.
I have plans to buy a Labradar, but I'm waiting to see how HAM does with their tests of the unit. So far, they've done okay with theirs, but the one I borrowed was questionable for airgun use. The nice thing about them, if they work as advertised, is they use doppler radar to measure speed downrange at multiple distances. This allows you to compute the real-world BC.