Engine tuning box

[Andy1489]

Hi Gents! I have just bought my 7th BMW an F30 330d 62 plate with only 18k on the clock. It’s a superb example however, I have just ordered a Spider tuning box which guarantees more performance. (And economy) I am concerned it could damage the engine. Does anyone have any experience with this type of tuning unit ? I have read many reviews on this unit and others but I have never tuned any of my others using this method.

Thank you in advance