The two I have, a pair of girls, I've named Matilda and Tallulah. I've never had pet rats before, but they are fun. They are easy to take care of in terms of maintenance, however, rat-proofing can be hard, harder than bunny proofing, at least in my house anyway.
I've had the girls a week in a half, and they are doing well. Matilda is more outgoing, but both take treats from me, climb into my lap, etc. Tallulah, however, will hide after a period of time out.
Anyway, if you've never had a pet rat, and you want something that is pretty easy to take care of and trainable, a rat might be for you. They are not smelly like a ferret either. They keep themselves very well groomed and do enjoy being around humans, at least these two. However, if you have other animals, you need to take caution with that. The other species may not be too happy with them, as evidence of Clover thumping for 2 hours after they got here.