It depends on the Octane requirement of the engine mate.
If it's meant to run on 95, then it's not worth using higher.
In fact, fuel consumption might be slightly worse, as the higher octane fuels tend to contain less energy.
however I would add a different viewpoint to what amount to basically the same thing - that is if you have aggresively advance the ignition, or raised the compression, or both - using the best octane fuel you can will increase your safety margin - SBD have well documented experience with the variance of pump fuels causing head gasket failure on engines in medium and above tune.
I would advise that you get yours optimally mapped for unleaded, and feed it on Super - it all depends on how much caution you wish to exercise - if you go for bleeding age map on optimax etc - and get a duff batch, or risk unleaded when you're out in the sticks... you might run into problems.