Radar Guns

Im looking to buy one because around were i live theres no one with radar guns and i want to monitor my velocity.
I saw one for like 75 dollars and i was just wondering if i can trust it and will it produce accurate results
http://www.radarguns.com/bushnell-radar-guns-101900.html

it might be 100% accurate, but it is better than nothng.

Ok thanks…

I’d say 100% accurate is what I’d be looking for. O.o

But what is the diffrence though?
Between the ones the scouts use and this one? The Stalker gun and the bushnell gun?

Does it matter if the ball sails above the gun or below it, will it effect the reading either way?