I have a portable, floor-support, and between-mattress, metal bed rail.
It's very sturdy. I pull myself up with it; roll myself to the side of the bed; exit the bed; position myself and steady myself when moving from Rollator onto the bed.
Height is adjustable. It comes apart for traveling.
Posts between mattresses nice and long for good support - doesn't slide out or move.
Feet on floor give extra firm support so it doesn't depend on the mattress to keep it stable.
It's wide enough across the top to grab with both hands if need. You can hang a removable bag from it for books, letters; cards/pens; meds, etc.
I only have one. Two would be extra helpful, but I only enter/exit one side of the bed. They can be ordered from different places.
Good luck with your selection. B.