Roberts sounds promising, but didn't Lowton get an assist at Southampton, on that basis it would be harsh to drop him. and if we're looking at changing players Lowts wouldn't be anywhere near the top of my list given his performances this season.
Our bigger issues are in the CM and striker departments, rather than at RB, however it's pleasing to note that if or when Lowton's form dips we've got a decent deputy who may well push him for the shirt when he gets his chance, which he undoubtedly will at some stage.