I've been running 26x1.5 Nimbuses on my Fisher Wahoo since August, and I haven't had a flat yet (averaging 75-100 km/week). I keep them pumped up to 80-85 PSI and they roll very smoothly. Even though I'm on an MTB, it's easy to maintain a 30-35 kmph speed on the flats without really pushing things.
I commute through downtown Toronto, and I've gone through a lot of

glass that would've punctured my previous tires (City Wolfs?). They're stable in the rain, but not so nice on hard-packed snow and ice (like yesterday, when I rode half the way to work out of the clips). And now that the redwall is grimy, they're not so flashy, either! Well worth the $45 CDN.
Jason