From my limited knowledge, that bot is more likely to have higher fuel consumption under constant speed cruising, and it is different then using smaller turbo engine for the same car (e.g. 2.0 na vs 1.6 turbo trim). The old turbo system is generally running at richer fuel so that engine is not overly heated at high boost high rev, I'm not sure on the latest tech in map/tune the fuel mixture. And i think ultimately the sifu will tune the engine to customer's need, like high end power or better torque or...

Emm... just hope that if someone, who is not very clear on something, please don't post statements like one knows everything.

I think, usually manufacturers' original setting is more pessimistic to cover the reliability in very harsh condition (tested in dessert or antarctic area), that some people got the ecu re-mapped to get better fuel consumption (maybe ignition timing earlier/air-fuel ratio to lean,... ), what ever car it is. Maybe some tuner is crap, but it should not be all.