I used to own one of the older carbed F650's.
The DL's finish is about as good as that was - i.e. better than the newer 650GS's.
The cast wheels on the DL are pretty tough, you'd be bending rims on either bike at about the same point. The spoked wheel MIGHT be cheaper to repair, but check it before you let that make the decision for you. I pretty much ignore urban potholes and "speed control measures" on the DL - BUT - if the roads are as nasty as you say, budget $300 for heavier springs for the DL.
On road the DL is better than the F, except on really slow tight corners. The speed difference is more than stated above - the DL gets up to 100mph + speeds pretty quickly, the F won't. (Quite a lot more passing power).
Off road, the F was a bit more nimble, the DL far less effort - note I'm talking nasty dirt roads here, not single track.