Opinions are opinions, but I'll offer mine. The components required to assemble a reasonably adequate radar detector yourself come to more than the retail price of that unit. That by itself may not mean much, but reviews of radar detectors, such as that published annually by Road&Track Magazine, Motor Trend, and others, as well as web-based radar detector reviews either ignore the RadioShack products, or rate them at the bottom of the pile. I've never seen a sub-$100 radar detector receive even marginally acceptable reviews. Personally, my choice is the Escort brand Passport 8500 model. About 6 times the price of the one you mention, but it is uniformly top-rated by all institutional reviewers, and it works.
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