I currently have the MX4 hard tri-fold on my Silverado. I love it. But when I get my Lightning, hopefully next month, I think I’m going to get the X4S.
One thing that I find annoying with the tri-fold is that my tailgate has to be closed before closing the last flap of the cover. The cover sits on top of the closed tailgate. If I were to open the tailgate, I have to lift the cover, close the tailgate, then close the cover. I’ve had my cover since about 2015, so I might have an older version. And maybe they’ve changed that on newer tri-fold models.
However, with the X4S, you can close it either before or after the tailgate. I can open the tailgate with the cover closed, throw something in the bed, and shut the tailgate, all without having to open the cover.
It’s a very minor inconvenience, but I thought I would mention it. I would still buy my cover again in a heartbeat, but want to try a roll version, hence why I’ll get the X4S for the Lightning.