They're not that great. I've received three, and I've been giving them away. The only one I still possess is in the emergency kit in the car, "just in case".
One came in with the knob falling off. On opening it up, I found that the knob mechanism snaps together, and it had fallen apart like a cheap Chinese toy...which isn't far from what it is.
Hey, it's better than nothing, but unless money is super-tight I'd get something better. A better cheapie is
this one, also available at CSI. You can also find it at other places, such as MCM, usually under the Velleman brand name (DVM850BL). The Velleman version has a dark gray faceplate, not the lighter one pictured on CSI's site.
Spec-wise, they're pretty much identical, with the CSI "free" meter having a slightly wider range in some instances. The big difference is that the free meter's build quality is crap, and it's a lot bigger and heavier. I'll sacrifice dubious features like a 20 MOhm measurement range for a smaller, better built meter. Also, the Velleman/CSI meter has a backlight. Woo.