Well, the 0-60 is impressive at 3.5 seconds, whilst i'm not quite sure where the £80000+ was spent. Somebody will be getting a cheapish performance track car to have a lot of fun, considering the supposed build cost.
I hope you don't loose too much faith in the project. Its been very interesting reading to now, whatever route you decide to take, what you have done so far is excellent and I'm sure you will make the right decision.