i dont have G25 but i did try it out at my mate's place last weekend..
it was AWESOME...
love the way of changing gear with a clutch and the H-shifter...
but i reli need some time to get used to it..
i like cant handle the clutch, heel-toe, shifter, steering at the same time..
i like either out-brake myself every corner or i braked perfectly but like forgot to steer so i ran into the grass...LOL
but i reli like the G25 to be honest...just LOVE IT