My rad must now be approaching 10 years old, (Build date roughly March 2001) and it is fine. A colleague had to change the rad on his 03 Astra a couple of years back as it started leaking. Anyone know if there is a normal "life" for a radiator? At least in my case, my Allard FMIC protects 80% of the rad surface from stone chips, etc.....

We've replaced a few, they tend to leak through the seals at the sides where the horizontal tubes fit into the side tanks. If you keep your cooling system in good condition and change the G12 when its due (around every 5 years), it should last for a long time to come. The radiator in my car is approaching 20 years old with no sign of a leak.