My son talked us into getting him a few rats. At first the thought of them left me cold. We went to get the rats from a "rat rescue" lady. I noticed she interacted a lot with the rats. That was important. I've come to appreciate that with small animals, human interaction when they're young is absolutely critical.
If you get a small animal from a pet store, they may have very little human interaction and as a result don't make good pets (nervous and nippy with people). If they get human interaction when young, they're calmer and less likely to nip people. We've had hamsters both ways.
Back to the rats. They're actually active, curious creatures, and in their own way "cute". I guess I warmed up to them, I'm not a rat fancier, but they're OK.