I have put a 180 in mine and here is why:
1) I live in MN and it can get over 100 in the summer. This helps to keep the engine cooler so It won't over heat.
2) Lower engine temps helps to lower intake temps too. Lower intake temps helps with added hp, even if it is a slight gain.
3) this won't effect the car warming up since the t-stat is closed until operating temp anayways. it just lowers it by 15 degees.
4) It won't effect you PCM. There are no wired connections to the t-stat. If you were to put in a 165 t-stat you may get a SES light due to too low of an operating temp.
5) Lower engine heat helps prevent extended wear on the internal engine parts.
I'm sure someone can give more detail on this but those are the reasons I went for it. And for the price, if it doesn't work, you can always switch it back.