Think it will comes down to the model of G4 vehicle to buyI run a Maggiolina roof tent,, and will not realistically fit the Exp rack on the Sport !! too long and too wide, even the small version ,,removal of the side bars, (if possible) as Craig suggests, may help !! It fits on the Defender just fine
I moved over to the Maggiolina, about 4 years ago, after a season in a Howling Moon,, not impressed,, flapped about in any sort of breeze, once wet, stayed wet, just soaked it up,, poor valve for money,