I bought my 54 plate ST over 4 years ago with 21k on it. It's now got 52k and I've had 2 sets of tires and 2 Tensioners. When it sounds like a tractor growling then you need to get the tensioner, pulley and belt changed otherwise it'll go again in under a year (thats why I had 2!) 45mpg all day long and 140 mph on a private road!!