IMO the key to keeping them reliable is replacing ALL sensors, replacing all service items on a regular basis (fuel filter etc) and replacing key components that have degraded over time...like looms or fuel pumps.

If you are prepared to do that then they are perfectly reliable, even at double its factory power output.

I never had any of my 3 Cossies break down or even fail to start i don't think...i had issues like any other car but all were minor and solved easily.