I have a Retrax. No clearance issues. But it does use a lot of bed space in the front, even in my long bed.
It locks anywhere along the rail. How hard it locks is adjustable, and it is really just a cone-point set screw that dogs down into the underside of the rail. It stays where I lock it if I do my part on the adjustment. The full closed/locked position is more positive.
I hitch up, roll it up to within a couple inches of the pin box, and lock it down. Keeps stuff in front of the hitch dry and out of the wind.
As someone mentioned, I did have to modify my Reese release handle, but I would call that an improvement anyway. The stock handle sticks up way too high.
This pic gives an idea how much vertical clearance you will lose (less than 1") and how much bed width you will lose (about 1" per side).
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