The guide is a bit too general, especially regarding thrones. Throne height has to be considered, particularly with very young players. The minimum height is a major factor for players who are short. Also, the density of the padding is crucial, as a soft seat will become “hard” very quickly. Also, the post that is the sturdiest is the spindle type, which will hold all but the extremely large players securely.
Regarding ride tom mounts, the ball-and-socket type is the quickest and most precise way to get the toms into the proper position.