I havn't seen a but a few feet per second drop with them. I keep them as close to the cam as I can. I would imagine they would vary from bow to bow on how much they hurt your speed. I have heard some people say they clocked no change & some up to around 10. so I would say it would be safe to say anywhere from 0-10 would be realistic.

445 supermag if I was you I would stop too! I think a lot could be how soft or hard your cam is on how long they last. I still think that even at 200 shots that isn't good life for a 9 dollar product!