IMHO and i could be wrong, if you have a tune that calls for a 180 degree T-Stat then change it.
However I have had cars where I put a 160 or 180 degree T-Stat in and had issues with it overheating, when I changed the car to a higher degree T-Stat the overheating stopped. This was mostly in part to the T-Stat opening too soon and not allowing the coolant in the radiator cool off.You don't want a T-Stat that is opened all the time nor do you want one that is closed most the time as well. This was on a few cars that did not have computers or a tune.
This is a very minor upgrade that gets a lot of attention for some reason IMO. Yes I have a 180 but don't notice much of a difference driving around. If you autocross or go to the drag strip it does become a bigger deal. If you do this remember to adjust fan settings.
When I changed to the 180 deg stat it was a literal thing. The engine ran cooler always. When cruising on the highway I run right at 180 when in traffic and warm out I climb to 215. with the old stat which I believe was a 210 or 220 stat it just ran at the exact deltas.
Ultimately the cooler you can keep the engine, air and coolant the car should perform better - is it measurable - in ideal conditions maybe. Really I look at it as heat kills - keep it as cool as you can without upsetting the ECU.
Heat soak robs a lot more power than you might think. Now that we've had 90* weather here in Omaha I notice a significant difference in peppiness and power with the 180* thermostat installed. In order to get the full benefits of this mod you'll need to adjust to fans to come on sooner.
Car feels stronger (butt dyno) with the t-stat. Having a custom tune probably helps too though. My tune is dialed in pretty darn well.