O'Brien and Bashir get sent to Bajor for a medical emergency by shuttle, and take two hours to get there. I think it's reasonable to assume they were travelling around full impulse, I.E. 0.25c. So at warp 1 it should take a good 30 minutes to get there. A warp jump in an emergency makes perfect sense, and is clearly doable at warp speeds in excess of warp 1.