Once you get used to it it'll be fine ducksie .These things are trial and error We had one for a wedding present and I never really bothered with it until we were abroad in a house with no oven .
Now I wouldn't be without it .I cook stews ,casserole type things and joints of meat in it .For example I buy a joint of beef brisket ,bung it in with some carrots,mushrooms ,celery etc ,turn it on and leave it to do it's own thing for about six hours,. .It makes it's own gravy which you just need to thicken ,slice the meat ,melt in the mouth beef and you can freeze the rest for another meal .
Same with a stew ,shove all your meat( diced lamb ,beef ,chicken ,whatever ), veg and stock in ,thicken towards the end and bung some dumplings on top for the last half hour .It's not rocket science :)