Suppose I'm only limited to choosing one of them - which one is more effective in terms of getting more grip?

thanks!

 

a;sdlkfja;dljfa....what are you talking about? 25mm dif. offset? or wider wheel...or spacers?

 

i would say wider tire vs stance (achieved with offset or adapter) with less tire.. if that is what you are sayin

 

that is correct.

for example. . .
Two Z's have a pair of 255/40/18 at the rear. +25 offset.

Z no.1 puts on 25mm spacers
while
Z no. 2 mounts a wider pair rubbers - 275/40.

Which one will have a better handling ?

 

is this a serious question?

does the tire contact the ground or does the wheel? There is your answer