Especially relevant to Rover engined cars e.g. those of us with Ali blocks with steel liners.
I have been chatting to Ray Webb the boss of V8 Developments who are currently machining my 4.6 to have top hat liners. He says that we should use a 82C stat but if the temp starts to climb we should get the fan(s) on earlier rather than later. E.g. before 90C not after. I have historically switched one of my twin fans on when the temp indicates the wrong side of 90 and I know I will not be moving for a while. He says it takes more effort to get the temp down so try to prevent from rising in the first place.
I think the standard settings on the thermostat switch in the rad are far too high. Basically get the fans on sooner is his advice.
He suggested a Kenlow type adjustable switch.
Peter C