Like many of you, I did not like the idea of a bow quiver. The first one that I put on (years ago) was heavy on the bow and caused the bow to shoot to the left.
About 6 years ago I ran into a guy who was making a bow quiver, but wanted to sell his dies and some material. This quiver was a little bitty 3 arrow quiver and it had some flaws but it caught my eye. We bought his dies and have been making improvements and many new models since. One of the things that sets our (EFA) quivers apart is that they are made as lightweight as posssible so as not to have a detrimental effect on how the bow shoots or feels in hand.
A proper bow quiver will help to improve the accuracy of most bows, especially lightweight high performance bows like the Shrews, Strikers, Morrisons, Beeler, etc. They can also quiet down some noisy bows.
Last night I put a quiver on a bow that shoots darned good to see if I could get a little more out of it. (It was an EFA 4 arrow Navajo I Jumbo I with the "totem" and "wing" attachments.) Shooting 4 arrow rounds, I noticed first of all that there was a little less vibration in the bow. Also, even though the point of impact was the same, the groups were a little tighter. This bow was a Pinnacle riser with Black Max limbs.
To conclude, we make side, back, and pocket quivers also, but our bow quivers are my favorite for hunting, 3-D, or stump shooting.