If you look in the picture thread, you will see that my 15 22 has Magpul XTM Dark Earth rail covers on the sides, and a rubber ladder on the top and bottom. I have since removed the rubber laddders, for the same reasons that stated above this comment.. is that they dont protect the rails nearly as well. Also mine started to slighlty discolor from being placed in and out of the bag, shooting gloves on them etc etc.

The Magpul XTM covers are a hard plastic compound and snap into place, and offer VERY secure and durable protection. Where as the ladders are just pressed into the slots on the rails and while they do stay in place, they are easily snagged if they are not 100% pressed into place. Thus allowing the corner to come out and actually rip into a few pieces, as what happened to my first set of ladders. It all comes down to personal preference as they do offer a more rubberized grip ( obviously). But Id prefer protection over rubber grip any time. And if you have good shooting gloves, the rubber grip isnt a issue.