Will I damage my Android device by charging it using a generic microusb + car adapter? I need a second charger and a car charger for my Evo 3D and the same for my wife's Nexus S, but I don't want to pay exorbitant prices for them.  Will I fry or otherwise damage the devices using something like this couple with a cheap microUSB to USB cable priced about the same?  Will the devices complain about using "unapproved" chargers and refuse to charge like some iPhone models do with some 3rd party chargers?
USB, mini-USB, and micro-USB cables are standardized, the voltage and amperage are the same across all standard compliant USB chargers. As long as the charger is a standard, generic micro-USB charger then it should be alright.

That doesn't make it impossible for a manufacturer to create a non-standard plug that looks like a USB plug, but they're pretty much screwed up if they do so.