> Which is better 700x23's or 700x25's??
> Would the different tyre choices make much difference??
It does make quite a difference. The 25's aren't just about 2mm wider, they're 2mm taller as well.
As well as more grip, all that extra volume of air provides more cushioning. But they're usually
slower because wider tyres tend to be inflated to lower pressures.
For fast riding on a good road bike, 23's are more the usual choice (for summer at least). You might
want to use 25's (or even wider) for more casual riding - or for riding over relatively rough bumpy
roads, or if you or your luggage is heavy.
I like the Vittoria Open Corsa 23 because it's actually a bit fat for a 23 - so more comfy, but
still very fast. Expensive and doesn't last long, though.