Yes its what Spec-r use. I did the original research for Pete & bought the first core. You get what you pay for im afraid not all there cores are good & they do a lot of cores. Pete wanted the most efficient core at a £600/700 price point. The one I bought for mine was more expensive for that & is thicker than his normal ones. I had to move the front cross member 4" forward & modify the head lights but it was worth it.
Its the most under developed part of Cossie Tuning by most Tuners. Give me a £2000+ price point & there are some really efficient cores out there .


As for Pete being the worst business man in the world & very hard to get hold of, I agree but Mark Shead is no better on time scales. but I think my car proves you wait for the best however long it takes .