To put things into perspective my belts were overdue on my ZS, I was pushing my luck as the mileage was low but age was the factor. When they were removed they were in a bad way and cracking badly.
I have been in engineering all of my life and have used HTD timing belts etc in alot of equipment. They do last longer than stated but alot will depend on the manufacturing quality and maintenance carried out plus not forgetting the climate as that will have an adverse effect on its expected lifespan.
Okay so an engine can be bought for less than a belt change, but tell me this, do you know what you are buying?
As with any car that is getting on in years you get what you pay for and if you don't like the costs to maintain then don't buy it!
I have had mine 8 years and I will be keeping it and when the time comes for another belt change I won't hesitate to get them changed, better the devil you know I say.
There will be some positive news soon regarding belt changes for forum supporters