What 58 Winters said regarding the way it goes onto your back.
Understand that an important difference between top end quivers is design. Good design will see to it that the strap is contoured to the shoulder so the quiver hangs well. Good design will also set the strap attachment points to position the arrows, where they can easily be reached. HH Archery makes a fine quiver. Art Vincent, makes a better one, (my opinion), of the same type of quiver.
The ideal place to buy a quiver is at a meet where there are lot of dealers, like Denton. There you can try on quivers.