thats a gr8 news,
I have also travelled on same route this august,
But ur lucky to have pleasant weather.
Please rest assure a small first aid kit with u, car fire extinguisher, tow chain and battery wires with u, plz do carry a good torch along.
The best stay and the half way is rahim yar khan, you can find plenty of good hotels there.
Plz do note to cross interior sindh in day light, although its safe now but still try to clear that in day light.
Right now i am replying to this post through cell phone.
I'll mail you some other details on monday Inshallah.