Fountek FR89EX Fullrange review. Very similar to the FR88EX I tested.
Cliff's notes: Low sensitivity. Ok midrange. Bad outside of this. Some pretty wild FR for a "fullrange" above beaming. High HD below 300hz; use a crossover for sure no lower than this. And HD around the breakup regions. All these comments are pretty typical of *most* fullrange drivers and why I don't use them myself unless there's a real need. YMMV.