Hi Mate
Essentially In your position but more like EG vs EK but still my info will help j00 :P
Figures from the Honda.com.au site
VTi = 1050kg
GLi = 1013kg
Breeze = 1000kg
Si = Somewhere in between
Essentially the reason why personally I would go for a Si or GLi over the VTi is the fact that those two models dont have a sunroof - Saving a fair amount of weight. Im not too keen on them and id be doing an engine conversion eventually so the power is not too much of a concern
I believe the Si, like the VTi, has rear brakes. The Si also has power options just without the sunroof, as the Si was the top of the range model before the Vti.
For me, If i was to find a good condition Si with less then 130K km's for less the 6500, id get it.
Si is the best of both worlds i think . Power(DOHC - yes i realise its the same output as the vti - and no sunroof

(saves weight)
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