These things are not a good piece of engineering IMHO. I had one blow out in 2010, had the dealer put in another, only for this to blow out a few months later. Got another one put in under warranty, and it is still there on the car and working, (touch wood).
Fleet manager of: -
XJ6 Sport 2003 (X350)
MG Midget 1977
VW New Beetle 2001 (wife's)
Fiat 500 1.2 Sport 2009 (daughter's)