OK!
Myexperience is this. I live in Kanaduh!! and the requirement is high temp. for winter and low temp. for summer. Those four bangers run very hot..particularly in the summer. Therefore, if you run the highertemp. thermo you might possibly run the risk of overheating especially in the summer. In general, the cooler you run the engine, the more life you will get out of it. I know the winters are mild in your part of the country...been there...loved it. My best advice would be to use the low temp.
Now..regarding the emissions testing....my experience has been to run the engine hard before testing...get it good and hot....a nice fast highway run and straight to the testing station. Use good quality gas as well and maybe some "emissions pass" additive if you are a little nervous.
Overall, if the engine is hot when it is tested, there should not be any problems.
