I'm not going to tell you what to buy. I have a RAM Mega cab with a short bed and had a slider for 5 years now. Never had to engage the slider and I have gotten into some tight spots. I will say, I believe it depends on the design of the front cap. The corners of the caps on both of our fifth wheels were a cutback design on the corners (Not sure if that is the correct). Get the slider, everything RV cost so go with it. Over time, you are going to waste more money on things you wanted for the RV and never use them.