Hi claydog, you are the only one who can make the decision, I'm lucky my dogs are only left 3 to 4 hrs in any one period, but in the real world many folk will leave their dog longer, due to work commitment ect and as said before you have to put food on the table. Good luck with your choice of dog and I hope he/she brings you all the enjoyment and excitement often found in these fantastic working breads.
Regards
Carl