Phoenix, I hope that everybody found the right solution, but I will tell you that you was right to worry about low 25 degrees.. by common sense any car running near 100 degree (92 C) as long the year happen the car it's a headache ... the efficient and longevity have to be balance, them low the temp to 82 C (179 F) or 70 C(158 F it's a good option, and Easy to do it's... just go to amazon and search, get the best for you and change

180 Deg F (82 Deg C) Thermostat - MINI Cooper

also there are another option compatible for 70 C (158 F) like

Mishimoto MMTS-NEO-97L Dodge Neon/SRT Racing Thermostat

after you try, them let's me know ... you have to know that for snow Zone it's not a good option but for Caribbean and USA South it's good option.