Well you can lead a horse (or an ostrich in this case) to water....
Lol at ostrich. I currently have one of the most tuned diesels in the UK. I had a GTB turbo fitted before most people on here knew what they were.
I'll tell you what I'll do. You pay for the above company that your bumming, to map my car - If its quicker, more powerful, or drives better than now, I'll give you the money back. If not, I'll get my mapper to put it back to how it should be and you'll have a nice experience to write about on the internet