It really does depend on how much you like spending money. If you're like me and would rather spend the ££££ you would have to spend on an engine rebuild on such things as performance mods, more regular oil changes and not having to run your tyres down to the absolute minimum before replacement then GET IT DONE ASAP! They have a huge reputation for breaking.
If you see a snapped cambelt as an opportunity to take your engine to bits and clean and replace and possibly upgrade parts(I have recently been made aware some people do think like this!!), and relish the chance to recondition an engine head, then you can risk it snapping.
Many people have run engines well past belt intervals and not had them snap, many more have had them snap soon after the interval. Some have even been unlucky enough to have them snap between booking it in for a cambelt service and actually taking it to the workshop
Mine was done for the 1st time at 70K, i'm now on 103K.. I've got no intention of getting it done again till 140K.
Can we place bets on whether you'll make it or not
As I said before, each to their own.
Mine was done at 39k (car was not in my possessions at this point!)
I have just had it done again at 75k, it will be replaced again after ~30k. It will arrive at this mileage well within 3 years. Mine cost a bit more this time because variator was shot, £298 without waterpump at Alfa Workshop