Ok, got some Insurance Quotes from Bennetts on the following models with some discrepancies;-

Suzuki GSXR600 97' £104.55
Kawasaki ZX6R 98' £105
Honda CBR600f3 97' £174
Honda CBR600f4 2000 £105
Honda CBR600i sport 2003 £105

It seems like it's a lot more to insure a 97' £1000 bike than a faster £2500 2003 model.Hmm
I ran this quote through 3 times and arrived at the same results. Interesting!