Second on a Lenovo T430. Really like my MBA, but the Lenovo tics boxes the OP asked for:
1) Internal DVD, Check.
2) Durable, next to the Toughbooks, the X and T series are some of the most durable portables available, just search Youtube for videos of water poured on the keyboard, units knocked on the floor, etc.
3) Bang for the buck. Watch the Lenovo website, T430s can be had for $800.
4) Service, most (but not all) T and X series have three year warranties. You can add on next day on-site if you need it for less than Applecare. Box breaks, call Lenovo support (usually Atlanta based), do some troubleshooting, a tech shows up the next day with either a unit or repair parts.