I have a vertical chicken roaster. Mine works really great.
The phallic part lifts off and is inserted into the chicken. The bottom part of roasting pan has a center cup that the the insert fits over. I usually put a little lemon juice and chicken stock or broth in there. I put more chicken broth in the outer ring. along with some halved or quartered (depends on the size) red or Yukon Gold potatoes. The chicken is prepared the same as I would for roasting on a regular rack.