gti : wouldnt bother - i looked into it as well, as said the performance is like any other 1.8 zetec apart from 130 spec xr3i. The insurance is stupidly high, the same as an st24 and the st24 wouldnt even need to try to beat the gti!
As said get the si as it has the smae performance, 5 insurance groups lower, and add the half leather seats and sill extensions and you are there