I have both. They are really hard to compare because the STI was primarily designed as a range pistol while the DW was primarily designed as a carry pistol. Finish on the DW is way above that of the STI but the STI is built tight, has a good trigger, and is accurate (so is the DW). I actually find myself shooting the STI more than the DW because of the fiber optic sights. Recoil is low in both guns but the steel STI really soaks it up.
Jim's Rules of Carry: 1. Any gun is better than no gun. 2. A gun that is reliable is better than a gun that is not. 3. A hole in the right place is better than a hole in the wrong place. 4. A bigger hole is a better hole.