It is quite alot of money IMO...Especially as the website DOESN'T include VAT!
You could probably get hold of a turbo unit fit it yourself, fit a 4bar MAP sensor and then drive it to them and just have them map it...
Don't forget about the supporting modifications which will probably be needed, ie uprated clutch!
I do not doubt DSD build qaulity or worksmanship. I have their IC and pipe and it is top draw.