as a general rule there is nothing wrong with a refurbished speaker they're usually an item sent back under warranty and fixed by in this case kicker themselves just make sure you are purchasing it from a legitimate seller and im not sure what kind of music you listen to but im personally not a fan of the 18 if you listen to alot of music with real low rolling bass go for it but if you listen to much rock you probably wont like it also look at the wattage required to push the speaker sometimes you can get good deal on a speaker but will have to spend a fortune on the amp to make the sub work like its suppose to...hope this helps
