There are plenty of stories of both of them doing stuff on set, pranking other cast members and stuff.

And plenty of stories of both of them being super-nice to guest stars and one-time actors, making sure they had everything etc.

I haven't ever read anything bad about any person on that whole show except for that one actor who turned out to be a creeper (he had a three or four ep run as a guy trying to kill Dean for killing his dad who'd been a rugaru, and now I can't think of his name....).