They are awesome little creatures!
Very much like dogs - although I have a young female here now that acts like a little monkey, she can fling herself from one side to the other, catching the bars. Crazy antics, lol. I think she'd have been way too distracting for my pup when I brought him home, lol.
I was using "Leave it"/redirecting to keep my puppy away from most things (shoes, plants, etc) but when it came to the rat cage I actually interrupted eye contact instead of physical contact. And then slowly he was able to watch them, then get closer, then give a sniff. Now he's great with them. They love watching him chase his toys past their cage, lol.