Yep - the claimed power increase isn't reflected in the dyno plot. I reckon it indicates a max increase of about 7 bhp, not 15 as Wayne has claimed.
Also that dyno plot is the same one used by the Belgium HotTuning brand E30 extractors for sale on ebay.
So Wayne - to clarify - are these HotTuning ones you are importing? If not, why are you using their dyno graph? If they are, why are you claiming you're getting them made & you've worked for 10 months getting quality right? It's all good if you're bringing them in to resell - but I'd just like to know the true story. I note the Hottuning ones have a 10 year warranty too, not 2 years as you are offering.