macnmore

I'm in the market for a travel trailer camper/RV and one of the stores recommended I install one of these before purchasing the camper. I've watched some videos on this and it seems straight forward, but I've read I will also need to enable/program it in my truck to utilize it. I called my mechanic and he said he didn't think the 2009's require it being enabled. Can anyone let me know for sure what needs to be done other than the physical installation of the controller? Also, there are some cheaper ones at O'Reily's for around $70 or the OEM part ranging from $130-$180. Is there really a difference? Some are digital and others aren't...what's that do for me?