I use the Panaracer Pasela 27x1 tires on my Raleigh Competition, because 27 x 1 1/4 tires on that bike feel sluggish. They hold up Really Well and seem to have low rolling resistance at 100 or so PSI.
To give you an idea how tough they are, I run one of these same tires (27x1) on the front of our tandem with the Weinmann Concave rims, inflated to 110 or so !
Not on the back, though...
Glenn Jordan - Durham, NC