Rowanbud
If you can get hold of some 275's & the price is right then get them , they look alot wider than the 255's & you will protect your rear rims abit more as the tire sticks out outside the rim edge , Also if you look at the fit tire to rim at the moment with 255's fitted as Feb 11 said they look under size & does not look the same as the front . So i say do it & join the 275's club, Its the only way to roll

.
Cheers
Andy