The phrase "a slight advantage over" is correct and usable in written English.
It can be used when comparing two entities, indicating that one has a small benefit or edge in a particular context.
Example: "The new software provides a slight advantage over its competitors in terms of speed and efficiency."
Alternatives: "a small edge over" or "a minor benefit compared to".
Nafta does give Mexico a slight advantage over other trading partners.
Boca holds a slight advantage over River in the nearly 200 matches played.
In this respect, it is conceivable that the physically wounded may have a slight advantage over their peers.
According to most analysts, Thursday's announcement gave Ms. Gillard a slight advantage over her conservative rival, Tony Abbott.
And in a slight advantage over the other gardens, traffic noise is largely replaced with the happy screams of kids in two neighboring playgrounds.
And when it comes to curling Hammy has had a slight advantage over his rivals: this is the curler born with an ice rink in his back garden.
The new Cloud Player is available in two tiers, including a free version that gives Amazon a slight advantage over Apple.
Sunday's victory by Kobe Bryant and the Los Angeles Lakers aside, LeBron James owns a slight advantage over Bryant and the Lakers in wins and in production over the years.
This year, Gov. George W. Bush of Texas holds a slight advantage over Mr. Gore in national polls, although the vice president leads in some tallies of state-by-state polls intended to predict the Electoral College result.
Ranieri, for his part, accepted that Leicester have a slight advantage over their rivals through being able to concentrate on the league without worrying about cup finals or Europe.
Republicans could also have some reason to be concerned about Nevada, which has not been polled recently but where their candidate, the appointed Senator Dean Heller, maintains a slight advantage over the Democratic Representative Shelley Berkeley.
