05-06 ZX6R Front Tyres Profile

Apologies in advance if this is a question asked a bajillion times.
My ZX6R is due for new rubber soon. I had SPM fit me a 120/65 PP front per the manual on the last change (my first) but i was wondering if I can fit a 120/70 front. I might have had a 70 with the POS shinko's that were on it before (bike was bought with these tyres) but i dont remember the size. If I can, are there any noticable changes to the behaviour of the bike? I ask because I have been offered a good deal on some supercorsa's, and as i mainly commute, these seem ideal for me, only catch is they are a 70 front
thanks!
My ZX6R is due for new rubber soon. I had SPM fit me a 120/65 PP front per the manual on the last change (my first) but i was wondering if I can fit a 120/70 front. I might have had a 70 with the POS shinko's that were on it before (bike was bought with these tyres) but i dont remember the size. If I can, are there any noticable changes to the behaviour of the bike? I ask because I have been offered a good deal on some supercorsa's, and as i mainly commute, these seem ideal for me, only catch is they are a 70 front

thanks!