HDi Running Temperature

[me-tm]

Quick question for you lot.

My HDi shows just above 70 on the temp gauge when it's warmed up, and the needle is completely off the bottom when it's cold (but that's normal anyway).
My question is, is 70 celsius or so correct? My old ph1 XUD ran at just over 80. The heaters still behave themselves and it all seems ok, but I'm just wondering if maybe the thermostat is slightly stuck open and it should be running a bit warmer, i.e. more like 80 celsius like the old XUD.

Thanks in advance!