Class 458
... that in 2004 the British Rail Class 458 trains were so unreliable that their operator considered replacing them all, but by 2012 they had become the most reliable fleet in Britain?
... that in 2004 the <a href="./British_Rail" id="mw2w" rel="mw:WikiLink" title="British Rail">British Rail</a> <b id="mw3A"><a href="./British_Rail_Class_458" id="mw3Q" rel="mw:WikiLink" title="British Rail Class 458">Class<span id="mw3g" typeof="mw:Entity"> </span>458</a></b> trains were so unreliable that <a href="./South_West_Trains" id="mw3w" rel="mw:WikiLink" title="South West Trains">their operator</a> considered replacing them all, but by 2012 they had become the most reliable fleet in Britain?