I would think a balanced theremostat would be best in any vehicle.
A drilled one would allow for coolant flow during closed periods which would result in less 'hotpsots' in the engine but a, probably not noticble, longer warmup period. This would not be bad or hurt the engine at all.
A 180 would be ok for the summer, but if you live where it snows then a switch back to a 195 for the winter might be recommended. Don't expect to run alot cooler. The thermostat only opens at 180, while engines are typically designed to run at about 200.
98 SSEi 111,222 miles.
Intense PCM, LS6 Valve springs, PEMS, FWI. Hawk Street Pads.