They are expensive when they break, yes - but so are GTA's
Surely its like saying "Don't buy a GTA, there's a possibility the cambelt could snap, leaving you with a big bill. Buy a 1.6TS instead, cheaper to fix"
Sounds like you have just been unfortunate - but I'm on my second car with xenon's, and despite the risk of a big bill, I'd still spec them. No substitute on the dark country lanes...