In the beginning God created crappola... and he called it the Mechanical.[>:] BUTTTTT..... they've gotten a lot better. I think the dislike is a lot of hold over from the early models. Also, a lot of people go to them because they're either lazy or don't know how to get a bow tuned so it will shoot fixed. At least that's the perception of some. I think the main reason for distain is that they steal energy and don't perform as well as a fixed on bone etc. But then, replacement blades have their shortcomings to. There seems to have been a disproportionate number of woundings and lost animals with mechanicals. A lot of that has to do with shot selection and placement. Also, people try to push the envelope and use them with marginal setups or below exceptable setups... therein we have more penetration problems with them. They are better and do work well if you're selective and do your homework. Me, I don't trust them.... but that's just me. My hunting partner whacks the heck out of deer with them. He has used several models with success. Still there are people that hate them simply because(as someone said) "they're mechanical". To each his own. If you decide to use them... do it wisely with enough K.E. to make them work.