Fellows, Len is correct when he said we got input from many,many, many shooters before we made a change. Muzzy is dedicated to its customers and always will be , we put you first. In saying that, when we make a change on the rest we do it in a way that if you change to the new product it is simple and it changes nothing as far as the set up of your bow. When you get your new rest there is a instruction sheet as well as a parts list inside, this is very important to you as the owner of the rest. If any thing goes bad due to poor quality or workmanship look up the part and call muzzy, It will be replaced. THERE are no internal parts to the ZE_Rest they are all external so you can see them at work. We will always keep parts here at Muzzy for all of the ZE- Rest which includes the LX, ICON, AND LEGACY from Matthews. Now, concerning the new roller slide, we are getting nothing but great feed back about it. If i can be of any help to any of you feel free to call me at muzzy. WE are alway looking at new ideas. Eric