I've heard riding with nice tires makes a huge difference in the ride. I have a Gator Hardshell on the rear and a Vittoria Zaffaro on the front. Just wondering if the GP will make that much of a difference?
I am riding on continental grand prix 4000s tires right now (i assume this is what you mean by gp4?). I have not tried the tires you have. However i have loved these tires. They are puncture resistant ( no flats since i got them last summer), durable, and seem to have a low rolling resistance. What i really like about them is the grippiness i get, even in wet conditions, in cornering. I don't know what your tires are like to ride on, but when they are actually worn, consider these as a replacement. Also They are pretty sexy in all black with the low key gray logo.
Bought one just now. I have a hard shell on the back for skidding but wanted something proper for the front. I've been riding that Zaffaro for over 6 months and it was time. The cornering with these GP's is outstanding. Love it. Other than toshi doubles, this is the most noticeable upgrade off the bat I've spent money on.