The slow cooker cooks it low and slow so that it gets nice and tender, so I wouldn't worry about it being up to temperature after 2 hours. (thefoodcharlatan.com)
Cover and cook on low for 8 - 12 hours (depending on how hot your slow cooker cooks). (livinginwbl.com)
I've been really getting away from slow cooker cooking as it seemed to leave everything I tried tasting the same... mushy and flavorless. (thelittlekitchen.net)