Hi there, if one of you can get home at lunch time to walk the dog then maybe it is possible, though personally I wouldn't leave a dog for more than 3-4 hours, indeed I do leave mine for 3 and1/2 hours each weekday morning though not before they have been out for a longish walk, I live on a farm so in the morning they are walked off lead around 4-5 fields, they are walked again in the afternoon for 1-2 hours again mostly off lead, I do obedience training with them also in the afternoon, what I am saying is that a dog needs a lot of attention, training needs to be maintained, but if you can fit it in with work and come home in the day then yes give a poor dog a good home, but if there is any doubt that you can commit to this then think again, most rescue centres are quite strict when it comes to someone being at home during the day.
Good luck with whatever you decide.