JD Powers study of 2009 models after three years of ownership ranks Porsche second.
http://www.thecarconnection.com/news/1072999_lexus-porsche-cadillac-top-j-d-power-2012-dependability-studyNote the 98 P-car problems per 100 cars versus 141 for BMW, 121 for Honda, etc. Lexus tops with 96.
No model differentiation in these figures so we can't tell Boxster vs 911 vs Pana etc.