Yesterday I changed out my thermostat for the 180 degree grey version. I was not having any overheating problems, but I did have a slight leak coming from the upper hose connection to the thermostat. Anyhow, the picture shows why I had a leak, the plastic had deteriorated and the lip was broken in three pieces. I suspect this was the original thermostat, I'm glad I changed it because who knows how much longer it would have lasted.

 

Also, I dunno if is just wishful thinking, but my engine seems to be ticking less?

 

My thermo gave out about a month after I bought my Disco. Mine actually completely melted out a 2 inch hole in the housing and looked like old faithful when I popped the hood to see why I had 3 gallons of coolant pouring out from my engine bay.