 I bought my 2003 model Prius in late 2002.  At the time only two hybrids were available in the market, the other was Honda civic.  I chose the Prius because it was roomier.  I had a major engine problem a year ago but thankfully was covered under warranty:  The fuel injectors were replaced.  Otherwise the only other problem has been the tires wearing out fast.  Make sure you get a warranty on tires.  