Overall The aqua is more fuel efficient by a good margin. It also has a very reliable Powertrain. It however has below average ground clearance. It’s not bad to drive but the Fit is in a different league.
The Fit has more value for what you pay, the interior looks better, materials feel better , seats are more supportive , has better ground clearance ,depending on the model you do get things like cruise control. It is a lot faster and more engaging to drive , it is however less fuel efficient and in the SL climate the DCT gearbox clutch can give trouble (discussed over the forum)