I have owned my S2 for 5 months now and use it everyday, never been unreliable. When i first got it i got pistons replaced(rings worn on no.3), head off, pressure tested(needed few new valves), a group A head gasket and got it set up on RR straight away and its never missed a beat. Starts first time and runs mint at 15psi. Do loads of miles but will be putting it away for winter as i dont want to drive it on gritted roads. (probs break down today after writing this lol)