I suppose it depends how you define "knackered". It takes about 20 seconds of cranking to fire up after a long lay-up in cold weather, subsequently it fires up pretty much straight away, it doesn't smoke after a few seconds of running, makes no untoward noises, uses less than a pint of oil between oil changes, doesn't leak oil or water and has run perfectly covering around 1,000 miles in the 18 months I've owned it. I certainly wouldn't dream of having it rebuilt or replaced just because it takes a bit of coaxing into life once or twice a year.
It doesn't start as readily as the diesel engine in my car, but then I wouldn't really expect it to.