Your nuts. I run performance's house brand of 26x1.25 and they're great for speed but for the way our roads have been around here they aren't wide enough to make me completely confident. I'm going up to 26x1.9 or 2.0 depending on the tire I get. I felt more confident even with 1.5's I used to run.
I can't imagine running narrower tread than 1.25".