I've lived here since a few years after graduating college in 1996. I lived in southern Massachussets right after college and I hated that more than Connecticut. I've lived all over CT. I lived in the southeast, the northwest, and now I live in the southwest in Shelton which is at the northern edge of Fairfield County.
The traffic sucks down here in Fairfield County. The Merritt and 95 are two of the most traveled roads in the country and it shows. One accident brings everything to a grinding halt. The only form of public transportation that is available here is metro north which overall is expensive and somewhat unreliable and available only in a limited area. Living near the train usually costs a lot more unless you live in Bridgeport (don't live there).
The cost of living in Fairfield County is astronomical. We bought our house in Shelton for $320k and that was a decent deal. It's a five bedroom two bath colonial with an acre of land and about 2000 square feet of living space. It was appraised at $400k after one year of us living in it. We did nothing to the house in that time other than paint the interior walls and have the hardwood sanded.
Which brings me to the only good thing about Fairfield County, the real estate. Unless you buy in Bridgeport your home investment is almost guaranteed to go up in value. My relatives bought in Greenwich back in the 70s and their home value has gone from $200,000 to over $3 million. Renting down here sucks ass, it is expensive and crowded. If you plan on spending more than five years here I would buy as soon as possible.
The weather here is terrible. Winter seems to go on forever and summer is hot and humid. Spring and fall seem to pass with extreme rapidity.
All in all I'm looking to go further south as soon as possible, but like I said it could be worse, I could still live in Mass.
Don't take a job that puts you in Fairfield County unless you are making over $50k or more. The cost of living will eat you alive.