Interesting .... I just got their "super stat" which apparently opens sooner and "throttles" the flow more so than a conventional type.
If at stat started to open at 180 it would probably depend hugely on the performance of the rest of the system how close it would get to fully open at 195.
I think thermostats do the opposite of what most people think. They don't keep temperature down to their rating, they keep temperature UP to their rating
Otherwise you could use a heater core for a radiator and put in a 160 degree stat
.
In other words ... they can keep your engine at 180 degrees if your system works well, but they can't keep it from reaching 250 if it doesn't.
I think the purpose of a 180 degree stat is not to make sure your engine runs DOWN at 180, from a design standpoint it's more to make sure your engine runs AT LEAST 180 .... if you take my meaning, as they are designed assuming your cooling system can handle whatever load the engine is capable of producing.