I recently moved to Attleboro and honestly love it so far. I'm about a mile from the train station and walk there 3 days a week to commute into Boston for work. Like a PP said, like any town, there are nice and not so nice areas (the area right by the train seems a little sketchy but I've never felt unsafe--granted my path is from the south of the train and as I understand, north of the train is where there has been drug-related crime).
It is incredibly affordable in terms of rent--I pay $950 for a large 2 bedroom apartment that's walking distance from the trains, restaurants, and a few grocery marts and pharmacies. I'm also about a mile from 95, which is very convenient. I love being close to Providence and am only 45 minutes to Logan airport (with no traffic). Foxboro is super close if they like football--I actually go to Patriots Place for my grocery shopping. They have the best Trader Joe's! Any stores you could possibly need are within a 15 minute radius of Attleboro.
North Attleboro also has a cute downtown area, and I like Mansfield too. Both are more expensive than Attleboro, and for me, being within walking distance of the train was important. (NA doesn't have its own train and I couldn't find anything in Mansfield).
What I love about Attleboro is that people seem to be out and about a lot--during that freak 70 degree day a few weeks back, so many parents were out walking around with their kids. People were just out enjoying the nice weather. I never really saw that when I lived in CT. It's really is a city with character.
OP, feel free to ask me any more specific questions!